Well in the position you posted White should probably play 4.d4 because the position after 4.Nc3 d5 (the point of playing 3...c6) 5.cd cd 6.Qb3 Nc6 7.Nxd5 Nd4 8.Nxf6+ gf is pretty good for Black.
But otherwise It depends on what you want to play really. As far as I know, the rule of thumb is that if White plays e3 when Black can play a sort of ...d5, ...Nb4 strategy Black will have a reversed Sicilian position that's better than usual. But White can still allow this kind of thing if he doesn't mind it. For example:
In positions like yours' with Black's bishop on c5 it tends to be ok but both sides need to calculate to be sure that the bishop doesn't get Black into some trouble if he tries to play ...d5 against e3 anyway.
Hello I am wondering about putting your knight on the e2 square instead of the f3 square in the english opening. Most lines have the knight on f3 but i feel like that blocks your g2 bishop. Are there any problems with doing this?