Airworthiness issues
I would not wrap an aircraft as I think it will hide serious corrosion issues and in aircraft that spend a lot of time outside it is likely to increase the speed that corrosion builds up.
If your aircraft is looking a bit tatty in the paintwork department a full strip prior to the respray will enable any corrosion issued to be addressed, wrapping the aircraft will just cover up the corrosion.
I would be far less concerned about wrapping a new aircraft that was hangared, but this is not the answer to old paintwork on an old aircraft that is left outside.