Hi Bruce. Why not do both
If your R&P is giving you trouble have you tried pulling it down, cleaning out the glue grease, regreasing and reassembling. You might find that that makes quite a bit difference to start with. If it's really bugging you then a crayford style focuser is very sweet to use. You probably won't even need motorising.
There are quite a few "crayford" style focusers around, moonlite and feathertouch (mmmmmm feathertouch arggghhh
) being right up near the top of the list (don't forget JMI as well). Have abit of a look around but both Bintel and Andrews (and I'm sure other Aussie shops) can supply crayford style focusers quite cheaply. Play with it for a while, then decide whether you want to motorise it. You would come out paying a lot less than for just a moonlite. Mind you if you get a two stage moonlite you mightn't want to motorise.