I think the 2 g3 english is slightly worse than the 2 Nc3 english as you kind of give away the setup you like to play.
This is because you are kind of forced to answer 1 c4 - e5 2. g3 Nf6 with Nc3 transposing into a mainline with fewer options to play for an advantage. The logical Bg2 runs into a favorable version of the keres variation after 3. .. c6 4. Nc3 - d5 and black is OK in the complications after 5 cxd5 - cxd5 6. Qb3 - Nc6 7. Nxd5 -Nd4 with compensation for the pawn.
so, I play the 2.g3 english and the english is obviously full of transpositional opportunities.
Looking through Avrukh's 1.d4 books, im struggling to find a point at which is will be a 'favourable' transposition. Can some knowledgeable people gives me an example or two, so I know what to look for?
Thanks