Out of curiosity, I thought I'd look at what voting percentages to use to maintain a stable account voting power balance. According to my handy dandy LibreOffice spread sheet, here are some rule-of-thumb numbers to keep one's voting power in the 80-90% range.
Assumptions:
Each 100% vote drains 2% of your remaining voting power.
Voting power replenishes at a continuous rate of 20% per day.
My hacked-up formulas accurately represent assumptions 1 & 2.
Votes are evenly distributed over time (not very likely!)
Update: To extend the rule of thumb: looking at the curve-fit formula from LibreOffice today, instead of the playing with the graphs, that curve can be closely approximated with the simplified formula:
Percentage = 50 / votes_per_hour.
1 vote every 2 hours: Vote with 100% voting power
1 vote every hour: Vote with 51% voting power
2 votes every hour: Vote with 25% voting power
3 votes every hour: Vote with 17% voting power
4 votes every hour: Vote with 13% voting power
5 votes every hour: Vote with 10% voting power
6 votes every hour: Vote with 8% voting power
7 votes every hour: Vote with 7% voting power
8 votes every hour: Vote with 6% voting power
Here are the (integer) percentages to keep voting power as low as possible in the 80-90% range from 1 to 23 votes per hour and the fitted curve that LibreOffice found from them.