Yes, caster could be increased to allow easier steering and better tracking --- until you try to turn. Then too much positive caster can make it hard to turn the vehicle. All suspension and alignment settings are a compromise between control, ride, safety, tracking, etc. Any modification from factory settings will perhaps do well by one factor, but could be dangerous in in one or more other factors.
Truckers live behind the wheel, most RVers live in the RV and only get behind the wheel to change scenery.
Bob & Donna
'98 Gulf Stream Sun Voyager DP being pushed by a '00 Beetle TDI