> The many little pauses and delays in "Visual Studio proper" drive me nuts, and most of the features in VStudio each only serve a tiny section of users, while making the IDE slow for everyone (and TBH when I tried the various Jetbrains IDEs, they are even worse in terms of laggy UI than VStudio).

I don't know how long ago you tried Rider, but after more than a decade of using Visual Studio I had had enough of the lag, broken features and instability - I moved to Rider, and couldn't be happier. In fact, I'd say it's one of my favourite ever pieces of software. It obviously loads much slower than VS Code, but then in operation if feels snappier and never lags. I've also never once had a release version crash, which for such a complex tool is pretty impressive.