I feel like White should be at least a little better here objectively, and I think Black faces a thankless practical task:
1. White was more space (which you mentioned)
2. White has a better Bishop
3. Black's King looks more likely to come under attack than White's.
After 17 Rhe1 Be6 18 Kb1 (18 Re3!?) 18...Rec8, while I assume you wouldn't advocate playing the ...Rc5/...b5 plan automatically, here's an example of what can happen if Black does:
19 Re3 Rc5 20 Rg3 b5?! 21 Qe3 Kh8 22 Rf1 (followed by Rf4-h4)
Point being, White's attack has the potential to develop a lot more quickly, as the ...h6 hook gives him a target (which Black lacks on the Queenside).
Of course, Black can always try to bail out with something like 19...Qc5, when in addition to 20 Qf4, 20 c3 is probably good, as any ending like this:
is clearly thankless for Black.