Do not make an rpg. Not right now, It will only end in disappointment. I'm telling you, it's impossible at this level. I've been doing game development for years and I would still not dare tackle a big FF style rpg, even with a team. If you are making tiles like that, then please do yourself a favor and start with a small game idea to hone your skills. You will soon see that all the behind the scenes coding which goes into even a small game soon becomes a handful. An RPG is by far the most difficult game genre to develop, and even with a team it takes the utmost devotion and planning. I don't want to sound harsh, but I am 211% sure that this game will not get finished, or even to a point of near completion. Come up with a small original design with your team or on your own, and see how tough it is to finish just that.
There's some solid advice there, except that while it's not impossible, it is VERY VERY hard. My RPG is an 'RPG-lite' for the exact reason that I wanted to try something simple to actually complete a project. It's been 10 MONTHS and I'm barely past the first boss!!! There's the map, battles, saving, inventory, leveling up, equipment, cinemas, stats, menus, towns, npcs, shops, items, etc etc and that's for a 'simple' RPG!
I don't want to discourage you, but there's a reason most indie RPGs are made with RPG maker - all that stuff that comes built-in is a lot more complex than it seems!
Make something small, a one area/town/boss 'practice' RPG that has all the features of the other RPG you want to make (I'm using this technique even for a longer RPG - that's why I'm not much further than the first boss). Seriously, it will be way more work than you expect, not to mention that you'll probably have to rewrite portions of it repeatedly to get new features to work with the old ones. The benefits of doing it this way are by getting all the game's systems and features working one one area, it makes it much easier to test everything, and then if after completing it you feel like you'd like to continue, you have a whole engine ready for content, making the development of the next game/area much, much easier.
Also, development tip: when testing a concept (like your tile system), don't put a whole lot of work into something before making sure it'll work/be feasible. That way you won't have to redo a lot of work if the concept doesn't work.
And I have to also vote against using BOF screenrips. if you're going to put this much work into a project, I highly recommend making some actual tiles. It will be MUCH more rewarding to have (and easier to work with!) original graphics.