Honestly I have never used anything like that. Therefore, I am not really the best person to ask about using any kind of automated voting system. There are pros and cons to it. You don't miss your favorite author's posts but you also may be voting on posts that you don't necessarily agree with at times.
As far as running down your voting percentage, I would think targeting your voting at 40-50 full power votes per day would be ideal. If you want to go much more than that you should drop the voting percentage on each post so that you don't run your voting power into the ground. You can probably experiment a bit and tweak things to see what percentage and number of authors works the best for you before you finally get things dialed in.
Sorry I can't be of more help on the matter, maybe hanshotfirst can be more helpful with his answer.
Oh no problem, I just wasn't quite sure who to ask. Actually, from what I can tell you choose everyone you vote for except one per day they get to use as they see fit. Which seems a lot better than the other trails, but, I'll just have to give it an experimental run and keep track of it for a couple of weeks. My thoughts were that I would only put on the people that I would vote for no matter what anyway, those that I've found have A: consistently good posts, B: don't generally post more than two per day.
I'll just have to give it a trial run, thanks for trying to help anyway!