I mostly play 3 Bc4 from the White side, but have had my fair share of games
3 Nf3 g5 4 Bc4 Bg7 from the Black side (when I play 3 Nf3 as White, it's never the Hanstein or Philidor). I looked through a bunch of old KG posts, but they were mostly talking about Kieseritzky, Quaade, or Rosentreter gambits.
NCO gives:
5 O-O h6 6 d4 d6 7 c3 and now:
- 7...Nc6 8 g3 Bh3 9 gxf4 Qd7! 10 Rf2 (10 f5 Bxf1 11 Qxf1 Nf6 -+) 10...Nf6 11 Qe1 O-O-O 12 Bb5 Rhe8 -+ (Glazkov)
- 7...Nc6 8 h4 (I think we're now in Philidor territory, with 8...Bg4, 8...Nf6, 8...Qe7 as lines given; all look pretty good for Black)
- 7...Nf6 8 e5 dxe5 9 Nxe5 O-O 10 Qb3 Qe8! 11 Ng6 b5! 12 Bxb5 Qe4 13 Ne5 Bb7 14 Nf3 unclear
In addition, the depressed-KG-author-who-shall-not-be-named (hint: there's a children's song about his farm) gives
- 7...Ne7 8 g3 g4 9 Nh4 f3 10 Na3 O-O 11 Bf4 "gives White an initiative for his pawn"
- 7...Nc6 8 Qb3 Qd7 planning 9...Na5
- 7...Nc6 8 b4 Bg4 planning 9...Qd7
Summary is that I'd be happy as White with the position after 7...Ne7 or 7...Nf6, but not any of the 7...Nc6 lines. However...after
7...Nc6, what about
8 Qa4! Qd7 (8...Bd7 9 Qb3 Qe7 10 Qxb7 += / +-) 9 Bb5 a6 10 d5 axb5 11 Qxa8 Ne5 += / +- I guess there's always 7...Nd7 intending ...Nb6, but I think this would have the same problem as 7...Ne7, i.e. 8 g3 with initiative compensating for the pawn.
Is this line a reasonable try for White? Is there an earlier place to improve for Black?