The biggest issue I've seen with smaller boat sailors moving up is their being surprised by the forces on the larger boats and this sometimes highlights improper habits which they get away with on the smaller boat.
This is the exact opposite of my experience.
I sailed a Catalina 22 for 5 years on Barnegat Bay in every kind of weather, up to winds of 35kts. On a small boat, everything happens quickly, and any "improper habits" are immediately punished, harshly. You only take so much water over the coaming before you start to learn how to use all of your sail controls, anticipate the gusts, sail conservatively when necessary, and keep the stick pointing up. Likewise, listening to the outboard was so annoying that we'd often sail in light wind when everyone else was giving up and running their engines. I'm not sure we got away with much.
We recently moved up to a 27 footer, and in almost every way, it's easier to sail. It tracks better, things happen more slowly, and it's far more forgiving. We don't get thrown on our ear or get stopped in our tracks from every stupid powerboat boat wake. We can move to the leeward side of the cockpit to handle a winch without radically changing our heeling angle from lack of ballast. I feel like there's a wider tolerance for how we have the sails trimmed (not necessarily for ideal
trim, which is equally finicky, but the boat will move in something other than absolute ideal trim). Yeah, the forces are greater, but so is the mechanical advantage, so that's mostly a wash.
The only more difficult things about a larger boat for us are docking and learning a bunch of complicated new systems, like plumbing, an inboard diesel engine, etc. The actual sailing has been amazingly straightforward. We've even been beating some larger boats with more experienced skippers in our club races (on actual time), and I attribute almost all of that to the quality education that we got from from the tribulation of sailing a smaller, lighter, more responsive boat.