Can I get a in depth explanation Professor? I would like to know the details of player freedom, RPG elements and what things you can do in the overworld(rather linearly connected large zones).
Sure I'll give it a shot but this might be a long post.
Player Freedom: Sprawling open world with tons to do ( more on this later) and no set order to do them in or you can completely ignore it if you want. The free climbing and jumping and swimming make it so if you have the thought hmm can I get there chances are you can, and it rewards you for doing so.
RPG Elements: Has the foundation of a FF game with standard leveling, then has the tried and true Materia system form FF7 OG, then adds a synergy system that's a combo of Chrono Trigger and FF10s sphere grid system, also has the weapon mastery system similar to FF9 and to top it all off has a party level system that ties it all together and even influences story based content with how you synergies with characters in your party. Combat is fluid, engaging, a challenge, has variety and above all is fun.
Things to do: Countless, play cards (build you own deck, buy boosters, win cards, craft, fight challenging foes, seek out new NPCs and delve into thier backstreet through side quests ( my fave), help out the moogles, find life springs to learn more about the region, do the battle challenges in "VR for Chad to get new meteria or the challenging sommons, captur Chocobos, help the ranches. I could go on quite a bit but I hope you get the idea there is a lot ( for ref I have 100% the Grasslands and am about 50% through Junion (about 20 hours or so).
Just exploring an fully realized FF7 world and finding the Easter eggs is fun as well.