Okay, let's see how I do here.
First time answering a TCG question! (Yayz )
**Basics**
I'm going to start with a point on the Mankeys.
Blain's Mankey used to be a favorite of mine, as I always brought a few trick coins to the table.
Even with that in mind, I would still say considering Hitmonlee ( Undaunted ) would be advised.
![][1]
A hefty retreat cost, yes. Although, 1 energy gives it that convenient 20 powered move. ( Guaranteed ) And the reliable 80 HP is really nice for a basic pokemon.
Inserting 1 or 2 of these in replacement for 1 or 2 Mankeys will allow some variety into your deck.
Also, if you only replace 1 Mankey from your deck. Using a Primeape card is a good solution in place of a second Mankey.
![][2]
This is the one from the EX FL and LG series, and my favorite.
It's also the one that I think would blend best with your deck.
While hitting hard coming out with your basics is always vital, Being able to stack a few energies down on your Mankey, evolving it into Primeape, and already having a evolved pokemon arise from the bench is a great advantage not to give up too soon.
And....
That's about it.
All of your option cards look in place, and I can't say much about the rest of the deck.
Besides obviously, that it looks great.
[1]:
http://www.serebii.net/card/undaunted/52.jpg
[2]:
http://www.serebii.net/card/exfireredandleafgreen/28.jpg