Sourdough,
I think you will find that your RB .454 is a fine piece that is capable of shooting a full spectrum of loads.
My lawyer wants you to work up your own loads using the appropriate manuals and with caution. But since you have asked, here are some examples of what works for me. I am not telling you to go out and try them on your own.
For practice and inexpensive plinking I like 9gr Unique pushing any of the 240gr lead bullets, either SWC or anything that the cowboy action crowd uses. This is typically a 45LC load and pushing it any faster will probably result in lead deposition. You will want to experiment to see what your revolver likes. I can reload the casings about five times with this load.
For real heavy hitters try 320gr hard cast (Corbon) over around 18gr W296 (work up to about 19gr with extreme caution). Use only new brass with this load.
Another good hunting load is the Hornady 300gr XTP-mag (#45235) over 28.2-31.4gr H110 (per the Hornady manual). My revolver handled a 35gr load without apparent damage and that was one of the more serious mistakes I have made handloading (moved my scale up 5.0gr instead of 0.5gr as I intended). Use only new brass with this load.
A steady diet of full house loads will loosen your fillings but they are sure fun to shoot.
good shooting