You are 100% a candidate for a quality arranger.
Your timing is great, too because 2 of the "big boys" (Yamaha and Korg) just introduced new models that are making some very attractive pieces drop in price.
Start by looking at our "for sale" section here on synthzone. There's always some tasty treats there!
Good choices:
Korg
PA-900, PA3x, PA4x, PA-1000(new model)
Yamaha
PSR ... anything above the 910 series, really. If you use your Roland as a control surface, the pianos will sound fantastic. The keys on the Yamaha are very light, with minimal throw - lots of us hate the action, lots don't.

Good luck, and welcome to the Zone!