I have been most consistent with electric guitar strings. For 25 years I played Super Slinky 9's. Maybe about 5 years ago I switched to Slinky Hybrid 9's to keep the lighter strings the same, but add more chunk to the E and A string. Now I am playing Hybrid Slinky Cobalt's because I like the tone better. Maybe there isn't much tension difference between the 25 1/2 and 24.75 guitar neck lengths, but my hands handle the shorter length better in tension and feel. I played both scales about the same number of years. One thing that I do on my Les Paul is top wrap the bridge, it seems to give the guitar a little "slinkier" feel as well. I do most of this for ease of bending. Fret wire is also a big factor in bending.
On Bass, my Rick 4003, I used 45-105 for round wound for many, many years; settling in on Ernie Walls as well. They have a nice growl to them with a Rick. Just in the last 6-8 months I have been experimenting with flats. The first set of flat wounds that I bought was Rotosound 45-105; the tension on those was really high, much more than the same gauge in rounds. I was actually concerned because they seemed to be bowing my neck slightly. I took them off after a couple of days and then started really doing some research and reading up on rounds. I began to regularly hang out at TalkBass and read every thread that I could on flats. Someone eventually posted string tensions and rated the feel of most brands and gauges. I settled in on a lighter set of La Bella flats and really like the tension and feel of these strings. I miss that biting growl sometimes that I get with the round wound bass strings on the Rick, but I have a real nice McCartney-esque thump going right now. I guess I need a second 4003 to have strung with rounds as well.
What was said about Basses staying in tune better than electrics or acoustics, I have found to be true as well. When I grab the Rick 4003, 9 times out of 10 it is still dead on in tune. If its off, its not but by a couple of cents. The electrics and acoustics always need tuning. It has been that way for me on Deluxe Fenders, Gibson LP Standards, Rickenbacker 330's, Larrivee acoustics, virtually every guitar I have owned in the last 35 years.