definitely do all the oil/coolant feed/drain line gaskets and screens/filters.
If the housing/wheels are undamaged, you can benefit from the CHRA upgrade. If you already have a tune, upgrade the tune. If you don't have a tune, get a tune. That's how much difference it will make.
OEM turbos are fairly inexpensive compared to a few years ago. Prob have to send back cores tho.
6 hrs or so for rear turbo (bank 1), 2 hrs for front (bank 2) turbo. VC gasket, not sure, probably under 2 hrs? Some idea can be had from the valve cover replacement TSB.
Check/drain your intercooler. That will tell you if a catch can is needed for your car or not.