Mew, I used to be all against Mate Centers, but as I've spent more and more time watching the various goings-on in Bonfire, I've noticed that the perception of MCs being chronic caps-lockers is actually untrue for the most part, or has become less true over time. Most of these guys don't actually use caps that much, nor do they "spam" the chats-- their posts don't even come close to matching the amount of posts put out by the other roleplayers around them.
This said, I don't see anything wrong with them, so long as individuals are not breaking any game rules (one or two caps-locked posts does not a rule-breaker make, for the record).
As for lag, this comes from any group of users that congregate together-- this includes wolf packs, warrior clans, lion prides, or any number of roleplays or friends bundled up into a floofpile. Plus, Bonfire is probably going to lag, anyway, due to its compacted size and large concentration of users together and running about.
Even with my new computer, which usually runs the game like a river (thaaank you Toshiba), Bonfire still lags a fair amount for me, even when I'm sitting by myself. It's just the fact that even when someone is not in Local range of you, your computer will still render other users around you and out in the distance, and this is why you get so much lag. The game is just working really hard to render all of these guys for you to see.
So, there's my input on the lag experience, as well.
Now, while I don't see anything wrong with MCs, I do still prefer choosing my characters' mates by roleplaying them together over time, so I can see how their personalities in-character mesh, and then any good looks they might have just make the relationship that much more adorable in the story-- rather than just choosing someone for cosmetic appeal. Paws down, it's just the better way in my eyes.
But, if someone wants to just make a new friend at a MC and roll right into a cute new RP with their "mate," then I see nothing wrong with that, either.