Welcome to CasinoTripReports! Bill's Gambling Hall is a fun place with a great location! I have always seemed to have decent luck with the video poker machines there dating back to when the place was called Barbary Coast...
The $20 trick has been known to work nicely at Bill's. As long as they have availability, my guess is that you would either receive a nice room with a view of the Bellagio fountains, or one of their larger suites. The large suites on the 4th floor are exceptional with a dining area, sectional, and jacuzzi!
Please let me know if I can help with anything as you plan your trip! Best of luck,