Here's Kramnik-Chandler, 1994. Our games reach the same position after 7...O-O, and he won, so it's a good model of how to play. It looks like f4 was a phantom threat, so I wasted a tempo defending against it with e3. If f4 then fxg3 hxg3 I am perfectly fine.
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Also I had the idea of d4 rather then b4 on move 15. -- HotFlow
This goes against strategic principles, because I have an "attack on the queenside" pawn structure. Tactically, after 15.d4 e4 I dislike Black's advanced pawn cuts off my bishop and potentially allows advanced enemy pieces, so 16.f3 exf3 17.Bxf3 and now my e3-pawn is backward on a half-open file and Black has many logical ways to attack it.
Being a lesser player... -- HotFlow
Anybody who expends serious thought on chess positions is not a lesser player; if their rating is low, it shouldn't be for long!
[W]hat you would of done at 22 now you had time to reflect. -- HotFlow
22.Nxf4 to maintain material equality.
The moment I began to lose was 18.Qe2 and 19.Rfb1. I went from +/= to =.
Trainer: So how do you win?
Slim: I attack.
Trainer: And what do you do after you attack?
Slim: Nothing.
Trainer: Why nothing?
Slim: Because I never stop attacking.
I briefly considered a4, but decided it wasn't worth trying, because it could be countered, and my opponent had countered everything else. This thought was the loss. I should have continued to attack on the queenside! Even if my opponent countered, I might have managed to trade off a piece, dulling his eventual kingside attack.
This is a great game in a similar line. Seirawan is a worthy adversary who knows to play 7...Nge7 instead of 7...Nf6 to avoid a later Bxf6. After 21...Nb4! Black's position seems to hold until Andersson plays the remarkable (but principled!) sacrifice 22.Rxb4! and suddenly the position isn't looking so hot for Black.
I had ideas of Nf6, he would have to reply with R d8 to d7 to protect the bishop and get his rook out of harms way, maybe then exchanging bishops allowing your knight to come back to the powerfull d5 with no way for it to be removed. But he could also take the Knight leaving you with the white bishop. -- HotFlow
I considered these lines. As you say, he unfortunately would get the choice of whether to exchange bishops or knights. I think the a-pawn attack idea is better. Oh well. I think I will be ready the next time I encounter a similar position. Bring it on! 
I was defeated today in the Symmetric English in a blitz. I would appreciate any comments or suggestions. Mine are already included in the diagram.