Well, it dodges more than the early g4 lines, not in the least the Staunton Gambit. I don't mind playing those with black so I'd be playing 1. ... f5.
In my experiences with the Dutch Defense, I've always found the Fianchetto systems the toughest to crack. You set up with g3, Bg2, Nf3, O-O... Problem, as with any Dutch line, is black can choose his setup as well. Ne4, c5-Nc6, c6, d5, d6-Bd7/Nbd7, b6-Bb7, all sorts of things going on and I've just about played them all.
As for the Semi-Slav, I'm no expert on the white side of d-pawn openings (I don't play them), but a friend of mine plays this line religiously: 1. d4 d5 2. c4 e6 3. Nc3 c6 4. e4 dxe4 5. Nxe4 (etc.). In blitz games he uses 6. Nc3!? as surprise after 5. ... Bb4+