the reason for choosing 2.4 hours vote-windows is inspired by the EOS ICO by @dan. Also it has to do with not draining the bot for vote-power but have a more calculated boost. As you know there is a limit on 10 X 100% upvotes per in a 24 hour period so these settings are done initially to explore and we adjust as we move forward. If it was per hour, we would adjust down the %.
You can speak directly with us on http://steemspeak.com if you have any troubles or ideas for improvements.