The only other UK rolling stock i own at the moment are EFE's Isle of Wight sets. As for multiple workings, that's not what i had in mind at the moment, but maybe in the future. I have however, for now, retained the couplings in one end of the set.
That is a question for the future, but when it comes to motorized vehicles i'd prefer not to mix manufacturer due to the different motor characteristics you mentioned.
I am only asking this as the 101's have buffers on the inner ends, but did they have screw couplers by any chance?
Most of the layouts i run on have a pretty rural look, so that works for me.