I dunno, I like the rep system.

Maybe integrate likes into it? I think that'd be pretty cool. But then wouldn't people like like someone just for the sake of it was their buddy, or something? You could have someone who's been on the forums a year and have more rep than an active user who's been active for five years, for example, over a matter of time. Maybe do something like every ten likes = one point? And every rep given is ten, or whatever the current figure is?

Besides, you can check likes on everyone's profile. I like that you can see how many people give too. Reputation is secretive, and I really like that about it. You have bars, but any regular member of the forum wouldn't know what it was for. With a like, it's obvious. If anything, I can see (and have seen) likes cause more trouble than rep has done since the change.

And no neg rep or dislike buttons. People would just use them to be an ass. </3