If you had not seen that game, Inn2, what are the reasons you like that variation for Black more? And/or why do you find it more interesting?
Personally, I prefer to hold on the typical pawn advances as long as I can hold them without getting in trouble. I prefer to develop Black's pieces first and attack white's center or his flanks late, after seeing how white arranges his position. In most cases this is the safest approach since often White uses these pawn advances from Black to attack the pawns (they make logical targets) or to exploit the holes they leave behind.
I think White would have kept a solid edge after--
1. e4 c5 2. Nf3 e6 3. d4 cxd4 4. Nxd4 Nc6 5. Nc3 a6
6. Be2 Qc7 7. O-O b5 8. Nxc6 dxc6 9. a4 b4 10. Nb1 Nf6
11. Nd2 Bc5 12. Bd3 e5
13. a5 O-O 14. Nc4 Be6
and instead of 15.Qe2 as Delchev played, White would play
15. Qf3 !? (with the idea of Bg5! when ...h6 is impossible)
15.... Bd4
16. Bg5 +/=
and if
16..... Qe7
then
17. Nb6 +/=
White taking advantage of the holes in Black's position. And White may later have ideas of playing c2-c3 (after preparing with perhaps Na4) and using the Black pawns as targets.