hi,
surely allniche will answer this (about the cheters).
For ratio: you should always use 100% for all trades.
For return: this depends on your skim, aka the quality of your out traffic.
For example: if you are sure the quality of your out traffic is excellent ( you have high skim ), then your return cap should be moderate, I say 300 for the hour and 150 for the day.
If you trade more like volume ( your skim is low, so is the quality of your out traffic, however you send a lot more out to your trades than they send you ), then I would even go for 400 by the hour and 400 by the day.
hth