Long thread on best Indian in Taipei over here, still active late last year; you’ll want to scroll down to 2018 or so I suppose.
A useful link I already put up in that thread:
http://www.trickytaipei.com/indian-restaurants-taipei/
Not yet listed above in this thread: I like Amma’s Kitchen a lot, because they have plenty of South Asian options, which can be unusual here. Recommended by @afterspivak here. They’re on Facebook, but I can’t get the link to work properly without logging in to Facebook, and I don’t do that.