i love the XR2, cant wait for the new release, whenever i lok at it, i have a 'crisis' (watchers of Top Gear over the last series or two will get that

)
as for learning curves... everyone has their own. i already had good atmospheric flights, from flying IFR on FSX, and the occasional fully manual flight (using only trim), then for orbiter, it was:
get out the airy bit around the rock
basic manoeuvres (plane change, orbit maintenance etc)
earth-moon transfer
moon landing and launch
re-entry (DGIV of course

)
-=Gap whilst i worked out transx=-
moon-earth transfer
altantis launching
-==To Do=--
interplanetary (transx wasnt doing it for me, learning IMFD now)
my ultimate goal, a perfect journey using arrow freighter-
moon-earth transfer
meet with an XR2
transfer to jupiter orbit
approach and landing on europa
set up the best UGCO base evar!!!! MWUHAHAHA
still some more to do, but ill get there
well done so far, and good luck for the future!