I thought that if we have distinctive colorful tiers in post counts and reputations that it will be more visually appealing. I also believe that it will be more motivation to move on to the next colorful tier.
Now the problem with reputation is that they're already green and red rep. So since red is a warm color, and green is a cool color. The tiers with reputation could move into cooler colors. Such as Green->Blue->Purple. Neg rep would stay red.
The colors could change as someone hits 500 rep and 1250 rep or something like this. Or there could be even more tiers, and shorter reputation intervals.
Now post counts definitely need color in my opinion as it's very bland right now. The colors could be Black-Green-Teal-Blue-Orange-Red-Gold. Or anything really.
Like the rep intervals. It could be 500 posts, 1000 posts, 1500 posts, 2000posts, 2500 posts, 3000 posts, 4000+ posts.
I feel like this will be motivation to keep our forum more active. Keep people trying to post more and get more rep. Not to mention it will look nice.
Here's my reasoning. What do you really get beyond 1000 posts and 500 rep? Not very much(as far as I know). These tiers will keep people moving foward.