I really wold vote for Daphne, because they are a good couple and I enjoy seeing them together, but it was really funnier when Niles was married to Maris because as some said the storries were funny on perhaps why she couldnt be at a certain event. Also when Niles was married it had a lot of secret Daphne jokes like, I believe in S2 when Niles starts smelling her hair and he says "Is that forbidden?" and Frasier says "In every sense of the word."
"If I see the morning hours, I'll have one more yesterday. A dateline from tommorow 'cause I burned up my today.
If I get up to the top I know, I'll just go back downhill. Got a terminal future and it's time to write my will." -Dave Mustaine