Literally speaking, "should" is the correct translation in this context. However, in normal English usage, to ask the question politely, one would say, "What time would you like me to arrive?" (Colloquially, the "at" disappears from the strictly correct "at what time".)

dann kann man also umgangssprachlich sagen: "At what time sould I come/arrive...."? oder ist das unhöflich?


Vielen Dank!

I agree with Joe W - "What time would you like me to visit you?" is best. "Should" has a different meaning IMHO.