People always ask "Any questions?"/"do you have any questions for me?" at the end of an interview. What are good go-to questions for this?
Are there different strategies to take here when I think the interview has gone well vs. when I think maybe it wasn't my best interview? I'm thinking if an interview isn't going super well this is an opportunity to impress the interviewer more, and maybe if it is going well then I can use this time to connect on a more personal level. Does this sound reasonable? If so, what questions might fit those specific goals?
I think it's actually super important that you mentioned using the end of an interview to impress the interviewer if you don't think it went as well as it could've. You need to be really careful to make sure you don't overdo it here, but I've heard anecdotally that it's pretty valuable to mention if you don't think something shined through properly in the interview, and ideally you'd provide an example, say on your resume, as to why you think that's an asset of yours that wasn't demonstrated.
With that said, I think some good questions you could ask could be:
Ideally questions like those can reveal a little bit about the operational effectiveness of the company and the culture you'd be stepping in to. Never forget that you're interviewing them just as they're interviewing you! If you're about to commit a significant portion of your life to them, I'd definitely say you should be extra sure about them! Hope this helps :)