I don't understand, why not just do regular D&D?
Isn't AD&D supposed to be advanced D&D? So you would be able to edit your character and roll for stats and such, and pick feats, and you could include a short tutorial with information on all you need to play, it could be very successful.
I feel like limiting the options of the player and simplifying it this much isn't worth making it that much more accessible.
One of the things I don't like about this is how you describe armor class. Aren't you supposed to work toward a high AC, so you need a high attack roll to hit? and those acronyms don't make sense either. THACO? Why not just call it Attack, or To Hit. Much more simple and accurate to what it actually means.
Maybe you're using a different version of D&D, like before the split, maybe you aren't using 3.0 (imo the best version)
It could be soo good and rewarding to even just take a character to level 5.
I hope somebody makes a version like that.