I'm refining my options right now, hoping for call soon to 'lock down'.
Perhaps better to say what I am NOT adding, and why.
Privacy glass - I have it now and don't really like the look on a dark car (nightblue). When reversing, after dark I cannot see through either rear side window to judge going around a corner as I have to do to get in my own drive, so I open the rear window to see, I know I can look at the rear camera view but it's not the same as the Mk1 eyeball.
Bose - I have it now, it's OK but apparently not worth the £801 extra.
Sunroof - Will never use it, should make the car a bit quieter, with pebble grey, the interior will be light enough.
Smoker Pack - I like the recess for holding small things.
21" wheels - have had lots of 35 profile tyres, far too easy to kerb lovely wheels causing aggravation even if insured.
All weather tyres - prefer proper summer tyres, and will not venture out in snow and icy conditions.
LED's - the comments seem to indicate that Xenons are good enough, mine certainly are.
Comfort lighting pack - the few extra lights are not worth the cost.
Roof rails - we'll never use them, prefer the look without them.
Sports Exhaust - not worth the extra for noisy exhaust note, although I have it now and it's fabulous.
Sports Chrono - will never use it.
Connect + - will never need live google maps, and don't want the extra cost of another SIM contract.
18 way seats - side bolsters just too high and I won't be driving in a manner that needs all that support.
Power steering plus - most say it's not necessary and can be added later as a software update if low speed steering is too heavy.
Extras I WILL order.
Carmine Red, 19"(SD) or 20"(GTS) wheels, Air, Sat Nav, Porsche crest on headrests (SD), heated seats, Surround view, Sports design mirrors, rear section painted (SD),Auto cruise control, dimming mirrors, mech rear blinds, heated front seats, 14 way seats and the alloy fuel cap (only an option on a GTS) at £89 because it looks good.
My spec is for comfort, on an SD about £57,300, on a GTS about £63,100. Not sure whether to go GTS - range anxiety/higher VED but would love the petrol engine or stick with an SD - economy lower VED and adequate performance.
In my opinion, minimum spec should include Xenons and Sat Nav, everything else up to you, that will get you a GTS for £56,240 or an SD for £46,994, whatever you order - they are great cars.