I've known several couples, too, who took very different routes:
One set of friends decided to simply portmanteau their last names and mash them together. For some names it can work - they ended up with Gunterson, I think, which sounds totally fine. Part of their concern hyphenating was what to do when they eventually have children...
Another couple I knew, both of whom had very troubled relationships with their respective families, decided to just say fuck it and change their name to something totally new. They decided on the last name of a very close mutual friend of theirs who had helped both of them through difficult times even before they knew each other.
I'm glad my husband and I found what worked for us. That's the nice thing about getting gay married right now - there are no "rules" for this kind of thing. So you can just do whatever feels right.