> I’ve never used the standalone apps. Do they provide a better experience?
In my experience there is no difference in terms of slowness, no. The standalone apps are usually just bundled with more features for the specific use case by default and in some cases they have features you can't readily get in just IDEA.
As far as I know, the standalones seem to work better with SDK and tool detection (I guess IntelliJ has to try to figure out which plugins to activate)
Some projects with mixed languages (like a Ruby backend, HTML/JS webapp) I've had to kick IntelliJ a bit to get it to cooperate and find tests correctly
Someone else mentioned CLion, I think Rider also has features you can't get via plugin (maybe there is no .NET plugin..?)