So I had a 3 hour interview (met 8 people) on Monday morning.
Normally the final question for me is "what are the next steps in the process?" but I didn't meet with the hiring manager or HR during this round.
Would it be acceptable to shoot off an email like that tomorrow to the hiring manager? We were professionally acquainted before I began interviewing for this opportunity.
I don't know that it's a bad thing, but I also don't know that it would be strictly necessary. What useful info would you find out? That they're going to make a decision at some point in the future? That they'll get back to you with any questions?
I wouldn't do it from the perspective of needing to show that you're still interested.
The useful information would be Ideally what their time frame is. And I do think the manager needs to know I'm still interested and I have more questions for her.
I think it's perfectly reasonable to reach out and ask, including it in an email thanking the recruiter or manager for arranging the interview/the opportunity to meet with the team, etc. Good luck!