Do you have ship where you want a character to be with someone because you like him/her and not because she would be the best match for the other?
I've never thought about it that way. Back in the day I wanted Spike to be with Buffy, but that stopped a while ago and now I can't stand them together. I wanted to Spike to be with Drusilla in season 5. That was not best for either of them.
Do you think there is some inequality in the couples of the Buffyverse where one character clearly loves the other more than the other?
Spike and Dru. Drusilla clearly did not love him as much, even if you ignore her Angelus issues.
Do you think Spike, Wesley and S6 Willow are good matched for their love ones and if yes why?
Not even close for any of them. But Tara is the only one I thought should run as far and as fast as she could. In any direction. As long as it was away from Willow.