I almost exclusively work in C# and have never experienced the Roslyn crashes you mentioned. I am using either Rider or Visual Studio though.

> Like cross-project "go-to-definition" takes me to either a list of members or a decompiled listing of source code, even when I have the actual source code right there!

If these are projects you have in the same solution then it should never do this. I would only expect this to happen if either symbol files or source files are missing.