I'm kind of a noob, but as I understand it having a thinner mash shouldn't impact things too much. People who do BIAB often use ratios well over 2qts/lb, and their beers seem to turn out fine. It means doing a full volume boil, but if that isn't an issue I don't think there is a downside to being *over* the recommedned water/grain ration.
As far as the temp, I would guess being at 156 is also probably still just fine. It is a little high, but seems to still be in the range people aim for a mid-range beer body. Did it stay at exactl 156 the entire 60 minutes, or did it lose a couple degrees as time progressed? If it cooled a little I imagine that would work to your benefit.
I wouldn't worry if I were you, but someone with more expereince will chime in I'm sure.