I haven't noticed a change to skill gains - at a low skill, they always seemed to go up very quickly for me. If anything, it's taking me longer to get my sims to max a skill. It's taken more sim days to max charisma, fitness, and violin on different sims than I recall it taking before the patch. However, that could be because I'm finding balancing skilling, working on aspirations, and career requirements more difficult, mostly due to careers. I'm finding some of the career daily tasks are taking a very long time to complete, and my sims needs are harder to keep high as a result, making everything else more challenging.
My painting sim now finds painting fun. I'm not sure if it's trait related, or if painting is fun for all sims, but before the patch painting decreased the fun motive in my game.