An uprated pcv isnt needed.
Correct. Just make sure it's working or recently renewed, and the same goes for the DV. OEM rev G will be spot on.
In my experience, if you don't want to compromise too much but want a solid step up from Stage 1:
3" downpipe with decat or good quality sport cat (BCS or Milltek), or ideally a full exhaust.
Uprated fuel pump (Loba or APR).
R-Tech map. Label it what you want - 1+, 2+, whatever. You'll see a reliable 270bhp, lots of torque from low revs, and shouldn't have to spend too much to get there.
Intakes and uprated intercoolers are nice to have, but something I'd personally put in the 'not essential unless you're chasing numbers or going k04' category.
Just make sure the basics are right before you start turning the dial up.