Hi Mike,
I play the regular speed 9 man games on Poker Stars. I find them ridiculously soft up to the $15's. On occasion you might find some of the $15's regged up but generally they are easy money and some of the regs are terrible anyway.
I try to play most of my $15's after 6pm UK time in the week as most of the recreational players are at work until then. And obviously the weekends are great, Saturday and Sunday after 2pm UK time are softest from my experience.
Don't bother playing the anything lower than $3.50 because the rake is ridiculous even if the games are insanely soft you will be better off playing the $3.50's.
For bankroll it depends on your ROI.
For me personally:
$3.50's - 30 buy ins.
$7's - 40 buy ins.
$15's - 50 buy ins.
These bankrolls are based on my ROI which is relatively high because I focus more on quality over quantity so my variance is insanely low. My biggest down swing is <$200 in a 2k game sample.
The only thing to really focus on is your hourly rate. You have to find a balance between how many tables you play and the quality of your play and the point at which your hourly is maxed based on your skill.
For me this is usually sets of 12 which gives me 7.5 games an hour and my average profit is $1.70 a game so this yields $12.78 an hour pre rakeback.
Sometimes I'll play 15 sets but only if the games are softer than usual as this makes up for any mistakes I make due to fast decision making but with a 60 second time bank it's pretty sweet.
I would recommend sets over continuous play because this means you can hyper focus on the late game and bubble pawning due to having less tables. On average I'm usually left with seven games that go to bubble or later. Occasionally you will get what I call a "OMFG" set where you end up on 10 bubbles or further. Continuous is ok but taking a 20 minutes break away from your computer between each set is very important, fresh air, toilet break, drink/snack etc then a 5 min review of hands from previous set.
When I play continuous the quality of my play starts to drop after a while so that is why I prefer sets.
Woops long post!
Hope this helps.
If you need any more advice on reg speed games let me know.
PS: If you don't mind variance, turbo's are definitely beatable without game selection up to $7's. Game selection is recommended at $15's+. I can't offer much advice about these games since I haven't played enough.