You should specify which abilities are (Ex) and which are (Su).
Oops, I forgot to add those...
Push the Limits is extremely powerful and should probably be reduced to a certain number of uses daily.
Hmm, I strongly disagree, the user is going to be mainly using 4th level spells (albeit heavily modded from Metawand abilities) vs regular spell casters who will, by that level, casting 7th level spells...But you might have a point...
It also might make sense to have this progress spellcasting at at least a few levels (maybe ever even level?).
This might be a good idea, although it was designed for non spellcasters...but you're right, adding a few might be doable for those classes that want to specialize in wands but not lose CL.
Regarding the feats some of them are more balanced than others.
Extra Recharge is quite weak. With only +1 a day I have trouble seeing anyone ever taking that.
Actually, thats +1 to your effective CHA mod so a total of +5 charges per day. Seems ok to me.
Some of them also have wording that needs work. I'm not completely sure what you mean by Wand Savant's "You provoke out to 10ft. when holding a wand"- I presume you mean that others provoke attacks of opportunity with the wand on you?
You are right, I had a hard time writing that ability.