Hmm, I'm just speculating.
Triple R's system is good, though I don't think newly created accounts should immediately have the rep ability, since that's pretty easy to abuse. That's one thing the current system has right. Still, we shouldn't be able to base a system on it being unchecked.
Personally, I do think more rep should equal more rep power but the difference should be much smaller and gradual.
Instead you should have to make decisions! Greatly reduce the numbers of reps you can give initially and you may not target any one more than once a month. It was too easy to spam negs on someone.
Every time you level up a bar, you should be able to put points in 1 of 4 things:
+0.4% Attack (rep power)
+0.5% defense (you lose less rep)
-0.25% cooldown (you can give more rep)
+0.1% Exp (Each rep you get gains more experience points)
- Achievements. If you get negged 5 times in a row, you should get an achievement and for other random things.
In addition, all reps and negs decay over time, but no more than to 25% of their original value.
Oh wait, this isn't an MMO; just forget it.
Though if you made it a boring pointless grind, maybe people wouldn't care.
^ If you haven't noted yet, I am not serious. But I'd play this over many other things.