I’m planning to visit Taichung around end of August 2026 & wondering how is the LGBTQ+ community / life / culture is like there… anyone can advise?
Stop in Ximen Taipei first. You might not leave.
I’m heading there after Taichung… 
btw, I’ve read up on a few bars - is Commander D actually appropriate for a one-person visit?
Depends on the person, and on the definition of “appropriate”. I visited a few times and liked the vibe there - definitely naughty, fun, playful - and not threatening at all. Disclaimer: I’m a straight guy.