I do quite enjoy those types of systems. And the progression of more stat points to allocate as you go on is also fun. In the MMORPG games I have played this type of system is common(though there aren't always more points available as you go on).
Anyways it would be a nice idea, though maybe not the most original(I think I have even seen the 'stat levels' before). But then again it isn't like you can be 100% original these days, you are always going to draw from something. The deciding factor is if you put together a good combination or not. And it does sound like your combination is solid.
To tell the truth if you made a game with a 'classless' system that had the leveling process decided by the player I would probably be all over it. But that is because I so love The Fourth Coming and it does that sort of thing.
Something you didn't mention would be that perhaps you should have the skills(magic, weapon skills, etc) level up capable as well(maybe have the skills unlocked for learning when you hit a certain stat requirement). And yes I pulled from The Fourth Coming though doubtlessly it has been implementing thousands of other times.