It looks as though you're adapting my repertoire for White:
4 Pawns against the KID
Exchange with Nf3 and Rb1 against the Grunfeld
4. f3 against the Nimzo
Zaitsev against the Benko
5. a4 and 6. Ne5 against the Slav
Bf4 systems with 0-0-0 if allowed in the QGD
Staunton with Bg5, d5, Qe2 against the Dutch
It's a nice repetoire. None of the lines are unsound or bad, and they lend quite well to specialization, etc...since they still have amassed theory that's quite sharp. I've scored really, really well with this repertoire.
Regarding the Zaitsev, it's certainly interesting, and very little played, so you stand good chances of surprising people. You can reach some really bizarre positions, most of which are quite un-Benko like.
Good luck, feel free to ask more questions. Quite an interesting thread for me....