Cordless is very handy for site work where you may need to be mobile, but the battery power is inevitably a bit limiting unless you have a couple of 18 volt 5Ah batteries to chuck at it. Going for 110 volt isn't really such a chore - if you need to do lots of heavy planing then a bettery tool just doesn't hack it IMHO
Jigsaw blades? Generally use Bosch, Festool, Starrett or Lenox brands (and there's equally nothing wrong with Metabo, deWalt or Wilpu either, just that nobody I know sells them) and avoid cheap Chinese carp. Which blade type you need requires a lot more information than you've given. For example, if you want a jigsaw blade for scribing joints in skirting you can't do better than a Bosch T244D (no orbit), for fine cuts in veneered plywood then a Bosch T101BIF would possibly be my go to choice although a Starrett Dual Cut BU2DCS-2 might be a better choice if double-sided clean cuts are the order of the day, for fast cuts in softwood (rough) a Bosch T144D or T144DP would be good, deep joint cutting might require something like a Bosch T744D or even a T1044D blade, whilst intricate scrolling work would mitigate the use of a Bosch T101AOF blade in some materials. The choice is very, very wide