True. 3 - 4 months isn't very long...the things you mentioned are worth doing if you are going off for 3 - 4 years.
The cold environment might even preserve things a bit...
...which does bring up a point...if you do return to the car a few months later to resurrect everything, pick a warm day!
2009 ML350 (84K) - Family vehicle
2001 CLK430 Cabriolet (71K) - Wife's car
2005 BMW 645CI (124K) - My daily driver
2012 Mustang V6 (60K) - Daughter's car