it allows you to evaluate expressions at fly
it allows you to back in time (move e.g 2 LoC above)
it allows you to use the Immediate window to debug and evaluate expressions, execute statements, and print variable values. The Immediate window evaluates expressions by building and using the currently selected project.
For example, I always found "edit and continue" really flakey in VS - it was really slow, sometimes using it resulted in a long hang or an outright crash, and quite often the IDE wouldn't even give me the option to use it. Rider is rock-solid by comparison - I'd say VS (with ReSharper) and Rider are roughly at feature parity, but Rider kicks VS's arse on stability and performance.
Another thing I'd add is that all of Microsoft's UserVoice-type feedback sites are an absolute joke - you might as well be piping your ideas into `/dev/null`. I feel like JetBrains actually listens much more to what developers are asking for.
Huge fan of Rider, and actually JetBrains the company too.
Having grown up with C, then C++ I find C# as the best compromise: expressive language, garbage collection, good performance, non-fussy syntax. When C# first showed up it was painful because for every other thing you had to call out to native Win32 libraries but nowadays I almost never find myself doing that.
Over the years the team added new language/runtime features at just about the right time: tasks, async, dynamic, reasonably tasteful collections.
For me Visual Studio Enterprise is a big part of it as well. I like plenty of open-source alternatives but honestly VS is where it's at.