I understand where you're coming from with most of what you say. The one thing I would say though is the day-trading rule really isn't an issue if you treat it like a cash account. You're allowed 3 "free" day trades in a 5 day period. The only reason why cash accounts aren't subject to this rule is because settlement date restrictions preclude day trading to begin with.
I think you would find the "restrictions" in a margin account much more tolerable than settlement dates. The only caveat is if you're trading with less than $2,000 and aren't eligible for margin.