Jack of All Trades
I reckon you are right.. The XR is a pretty reasonable bike for all of those purposes... not very good at any one job but can do it all.
Back in the late 90's I had a 95 model XR600 with a CR250 front end on it, flat slide carby, exhaust, ported and flowed head etc. Used to ride it to work, trackdays, flat track, rides all around south east QLD (dirt and street). Had a set of dirt wheels and also a set of wheels for flat track (18inch rear with wider rim, and 19inch front rim).
At that time there was still a class in roadracing for Harley Sportsters...with 19" front wheels.. used to pick up 2nd hand Avon race tyres for free from the sporty guys, and use a dunlop GPR70 on the rear.. sort of semi supermotard.
Once the corners got tighter, the boys on proper road bikes could not keep me in sight.
I still regret selling that bike!!!!!!!!!
Have fun with the build up.