Okay, most of this is probably going to be a reiteration of what everyone else has said. BUT. I think it needs to be said anyway.
Others have already pointed out the vagueness of the battle system and the redundancies in the class list. Beyond those, I have two major gripes with this:
1) What do the jobs do? Like, wow! A time mage sounds cool! But what...does a time mage actually do? Hastega? How would that translate into RP combat? Similarly, FF has spell tiers, e.g. ファイア、ファイアラ、ファイアガ、ファイアジャ (aka Fire1/Fire2/Fire3/Fire4 or Fire/Fira/Firaga/Firaja). Is there a system in place to stop people from loading up with tier 4 spells at the start of the RP? How do they unlock later tiers? Is there a skilltree for the classes? What exactly does the class system entail?
2) The plot. This is my biggest problem with what you've outlined, there's nothing about the plot. I have no idea what's going on or where it takes place. For instance, you state this RP occurs "In a world where a great war was clashed by friends and foes alike". Ignoring the misuse of the mono-transitive verb "clash", this description tells me nothing about the world. Is it a desert world, a la Kashykk? Is it a frozen Tundra, like Niflheim? Is it metropolitan? What's the technology level? Is it an intersection of worlds, like the plane in Dissidia? If so, by what rules do these worlds intersect, and why does this plane exist? You need to explain the setting. Right now, I literally cannot imagine anything of the world you're trying to construct, because there isn't any information to extrapolate from. And if a person can't visualise the setting, it'll be nigh-impossible for them to achieve the level of immersion needed to enjoy an RP to the fullest.
Adding on to that, you have not mentioned anything of the plot. Let's say a player were to join your RP; what would said player be doing? Is there a goal? Is there a storyline? How did the player come to be in this place? Is he part of a merry band of heroes? There's no information given about this. I'm not saying you should outline the entirety of your intended plot, but the players should at least have some semblance of an idea about what they're signing up for.
I would suggest looking at the OOC/Signups threads for other RPs, to get a better idea of what is expected of a host's OOC topic. In fact, in my limitless generosity, I've picked a few for you to glance at, and even listed what they did well! (IMO)
ANKL, by Lexi (Worldbuilding, Character Creation)
The Tenth God, also by Lexi (Worldbuilding, Battle Mechanics)
Fire Emblem on the Forums: Ashes, by Pyon (Worldbuilding, Character Creation)
Luminous Dawn, by Jory (Battle Mechanics)
Heartless Souls, by Hukuna (Character Creation)
Sins of Avalon, by Stratos (Worldbuilding, Battle Mechanics)
The RPs above all have wonderfully crafted opening topics, and can be very good references for the level of effort and preparation which RPers expect of hosts. I would suggest taking a look at them as a starting point for polishing up this idea.