Ryan,
I am probably not in a position to give advice as I have a little less than 5hrs logged but I can appreciate where your coming from (although I avoided flight sim prior to starting but have bought it to install when I get to instrument practice as its cheaper than flying).
The way I am being trained is to keep looking out and have the instructor tell me when I get to 20degrees or 30 degrees depending on types of turns we are doing. I then get asked to hold it then by mentally marking the points of where the horizon cuts across the front window and get used to that (Not easy on a hazy day). It was explained to me to use the real horizon in the windshield as you would the artificial horizon and correct based upon that.
After getting it sort of right my instructor then asks me to look around outside scanning for traffic and return back to looking out the front window and correct if required - I am told judging the bank angle visually is something that comes with time as is adjusting the throttle by engine sound and not watching the RPM.
Cheers