Setting the reward limit is a feature present in nearly all front-ends, not just D.Buzz. For people starting out or who have been around a while but have a maximum vote value less than some number (say, USD 2), it should be set to 100%. For people whose maximum vote value is massive (e.g., USD 100), the vote value can be scaled back. While there are some buzzes which deserve lots of upvotes, are they worth an upvote of USD 100? So that's why that setting exists.

As for the UI, it has rough edges, definitely. If D.Buzz can get the functionality right on all the features it has, I can wait for the rough edges to be smoothed out.