If anyone wants suggestions for their home cockpit, they should look no further than @skypilotYTS’s setup 
(I think we all need an altimeter clock, BTW!):
In all seriousness, if you hadn’t mentioned that you were looking for throttles and stuff, I would have said that the cheapest upgrade for any home cockpit would be haptic feedback, like a Buttkicker and SimHaptic software.
Since you mentioned throttles, rudders, and stuff, what do you fly? GA? Multi? Single? Turboprops? Clearly you fly Airbuses…are you happy with those? Are you looking for something to use for life? Or do you think you’ll do this for fewer than five years and move onto something else?