Well, of all laptops, Macbooks tend to keep their resale value up the best so buying now and reselling later isn't necessarelly a bad deal.

Sure, holding out makes sense if you need the upcoming models but at the moment their best features are rumours.

I'd call the new CPU almost a given, we know Apple had several SoC versions on their table but beyond that, which models will make the release cut this year is a guess (some bigger screen MBP, sure but I'd be surprised to also see an MBA)