They're upset for reasons they
think they understand. They don't realize what you're trying to do, which, to me, sounds like a great idea. Once I get my character up and running (I've only got a name down, so far), I'd definitely feel more welcome in a LMC than a regular MC (god, those things are barbaric, they're only slightly amusing when the MC host is shouting "WHO WANT SEXY M/F?!??" as if they were hotcakes).
From what I'm reading, it sounds like you're trying to make the matchmaking process more civil or professional. A place where a person's character isn't treated like an object and everyone's given a fair chance to put their best
foot paw forward, so to speak. People don't
have to pair as mates, but it would be something to consider since it's generally a "mate finder" kind of Center. Again, it sound a lot more welcoming, and as long as it stays that way, newcomers (like me) will always have a safe environment to make new friends and RP buddies (while possibly fetching a potential mate for their OC).
If you're worried about the whole "MC stigma" nonsense, sometimes it's better not to listen to them. If you want to make a difference, keep that foot down and don't let people boss you around. You made it clear that you're trying to help, and if they don't like it, they can bugger off.
If you ever need assistance with your LMC and I happen to be around, send me a whisper.