Orust system with Silflex seal for the Neck seal
Dry Suit Option - Warm Neck Standard
I think this combination is not possible. If you want want a warm neck option, you must choose Quickneck. I am happy with Quickneck+simple warm neck combo.
Leaning toward no P valve, they just seem unneeded for more rec style use and a bit of maintenance I don't need
P-valve is also easy to add later, unlike most other drysuit options.
SITech Valve System (including hose) - Would love feedback here between the standard and the SiTech
Honestly, no real difference. Apeks low profile dump valve is lower profile than any Sitech and somewhat easier when donning gear. Some people claim Apeks low profile leaks, but others like me don't have that problem. All dump valves can leak a bit in certain conditions.
I use Apeks on all my suits, but Sitech users are equally happy with theirs.
Expedition Pocket - Both Sides - Would be interested in feedback on pockets, I like the flat ones, but they look limited in usability
I took large bellows pockets for simplicity, the expedition pockets are probably better. I'd recommend expedition pockets unless you really know that you want something else. If you ever plan carrying dir style equipment in your pockets (I mean at least spool+smb and mask+wetnotes) expedition pockets are not oversize and the large bellows pockets are minimum you need.