If it’s true that the Force belongs to everyone, then why not have the other main heroes in addition to Rey–Finn, Poe, Rose, and “Caro”–Force-sensitive as well? They can be Rey’s first pupils (though it’s more a mutual teaching/study group situation) and, going off the books Rey got from the Jedi Temple, develop their own theory and practice of the Force. Here’s how I envision their respective specialties and powers.
Rey

Summary: The generalist Jedi and melee combat specialist
Description: Rey has the most obvious and familiar, seemingly supernatural Jedi powers. She has impressive Force telekinesis, Force telepathy, has had Force visions and dreams, and the mind trick. She is a force, or should we say Force, in melee combat. She is the tank of the party and all-purpose Force powerhouse, not to mention a potent symbol to revive hope when the Jedi seemed all lost or fallen.
Rey still has limitations, however. While her abilities are very strong, they are generally obvious and one-off in nature. She can use the Force mind trick to get a Stormtrooper to take her shackles off her, but trying to use the mind trick in negotiation, for instance, would be noticeable and end up breeding distrust. Similarly, she can be a whirlwind of destruction in combat but can’t turn the tide of a large-scale battle on her own. She needs a team, and having trusted friends can in turn help her resist the lure of the Dark Side, which can be strong for a Force user as powerful as she is.
Finn

Summary: Empath, death sense, Battle Meditation
Description: A Force user on par with Rey, Finn has the ability to sense life and, less pleasantly, the ending of life. We saw him go into a panic attack at Slip’s death, seemingly sensing him die. We saw this ability again on a larger scale with the destruction of the Hosnia system, when he sensed the mass deaths much like Obi-Wan did. Highly trained and talented at both long-distance and melee combat, he has probably been unconsciously powering his military prowess with the Force all his life. He knows how to read a situation and people instantly and use this knowledge to great effect. Particularly skilled in small unit combat, he is the undisputed tactician of their group.
His tactical genius and empath abilities intersect for devastating effect in the form of Battle Meditation. He senses the battlefield and the combatants and, with a mental nudge here and a tug there aided by his own extensive strategic training, shapes the battle like a sculpture or a Rubix cube. The Resistance/Rebellion pulls off victories out of all proportion with their resources this way, especially with Finn’s extensive knowledge of the enemy. His strong empathy can be a liability as well as an asset, however, and sensing the deaths of so many people could result in trauma and burnout. He needs emotional support from a caring network of people, and fortunately he is no longer alone.
Poe Dameron

Summary: Force-aided instinct and reflex, micro-visions, inspiration
Description: A young leader of the Rebellion and Leia’s chosen successor, Poe has been using the Force unconsciously for his piloting much like Anakin and Luke Skywalker did. Sensing events in the split second before they happened gave him uncanny reflexes and saved his life in many a tight spot. Further developing these abilities gave him an edge not only in his reflexes but in planning and leadership as well. Sensing danger in advance helped him avoid costly mistakes and, conversely, being able to sense payoffs for risks enabled him to take risks in a calculating, advantageous way.
As Leia pointed out, though, he has to be more than the pilot or kickass spy he’s used to being; he also has to be a leader. With his deep roots from his parents in antifascist resistance, you might say rebellion is in his blood. He inspires others with this conviction, and being in the same room with him or even watching a holo of him speak can electrify audiences despite–or perhaps because of–his simple, down-to-earth style. It is one of the many qualities that his enemy General Hux, known for his bombastic rhetoric, scorns about him.
Rose Tico

Summary: Machine Spirit, shatterpoint, emotion sending
Description: Loving droid owners like Poe have always known that there was more to their companions than gears and electricity, and Rose’s awakening Force power confirms this. She can sense and communicate through the Force with droids and computers, including ships that are equipped with droid brains. The Force is the connection between living beings, after all, and sentient machines are just as alive as organics if in a different sense. Rose’s exploration into this side of the Force endlessly fascinates Rey and Chewbacca, both enthusiastic mechanics, and Rose’s insights into the needs of the cranky old droid brains that run the Millennium Falcon have done much to place her in its good graces.
Rose also has the Force ability of shatterpoint, rare and once thought lost. She can sense pivotal points where a single outcome may change the course of events. In this she takes after legendary Force master Mace Windu, and some have speculated that she may have family ties to Ghôsh Windu, Master Windu’s clan which nearly died out with him. When Rose risked her own life to save Finn’s on Crait she sensed a shatterpoint, convinced he had to survive that moment no matter what. It was more important than her life or the lives of the entire remaining Resistance. Subsequent events proved her right, and fortunately the grim payoff did not come to pass thanks to the intervention of Luke Skywalker.
On the flip side of Finn who is a strong empath, Rose is strong in broadcasting her emotions, particularly negative emotions such as fear and pain. Some of her occasionally unhealthy interactions with Finn may have resulted from their respective abilities going in a feedback spiral. Now that she is aware of the effect she has on others, Rose works hard to modulate her emotions and is particularly careful around Finn. Her friendship with mechanical sentients, who are less moody than organics, helps in this regard and she can frequently be found meditating in hangars and repair rooms while curious droids look on.
Caro*

Summary: Force echoes, life powers, shadow friends
Description: Caro thrives on the balance of all things, passion and peace, anger and compassion, life and death. Rey admires how she not only understands but lives the concepts that Rey herself has only begun to grasp. Rey, Finn, and the others to different degrees can talk to the spirits of powerful Jedi masters who live on in the Force, like Luke Skywalker, but Caro goes farther. She is not only more effective at communing with these spirits, she also hears echoes in the Force itself from every being who has ever been in the Force. Not all at once, of course, which would overwhelm any mortal, but she can sense snatches that she seeks or that simply come to her. She can attempt to get more information through concentration and meditation, and this was how she found Finn: Through the memories of people living and dead who had crossed his path. Slip remembered him kindly, Caro told Finn, though he still thought him an awful showoff. Due to her powers she frequently seems to know people before she meets them, which some find unsettling.
As befitting a Jedi who is a master of the Balance, Caro has deep connection to life as well as death. She is a healer of great skill like Barriss Offee before her, and has saved many lives. An expert at integrating medical technology with her powers, she has worked with Rose to pool their strengths for better medical care in the Resistance. Though Caro is more accepting of death as a part of the Force than Barriss was and has proven more resilient to the trauma of losing patients, she can be saddened by the mounting losses. Finn and the others take care to draw her gently from her solitude where the events of her life and her unique powers sometimes lead her to take solace. She is particularly loved by defected Stormtroopers who have never experienced such caring, and quite a few are open about being willing to fight and die for her more than the Resistance. She has found a loving partner in one of them and their companionship brings her much joy.
Through great concentration and focus Caro can cause these “echoes” in the Force to take temporary physical form. They can help with set tasks and even go into battle with her, although the effort can be taxing for her and their actions can be unpredictable. Such is the nature of the Force, and she accepts that. It is key to the peace and balance she keeps with the Force.
* Caro’s powers are purely speculative at this point, of course. We don’t even know her name, to say nothing of her abilities or relationships with the other characters. But it’s fun to imagine and there was no way I was going to leave her out of this post, okay?