To me, the roughness and lack of polish / mastering is part of the charm of using Sonic Pi instead of a DAW. I feel more connected to the music when I’m working with the raw sound on-the-fly. Trying to do something refined in Sonic Pi seems a bit like forcing a square peg in a round hole. It could be an interesting challenge to build something out of it, for sure.
That being said, if you want the algorithmic composition but with proper mastering and refinement, you might be better off figuring out how to make Sonic Pi control things inside your DAW. I’m not sure how to do that, but I would be very surprised if no one else has tried to approach the problem before.
You could also look into the different OSC tools out there and use that to control the parameters of your synths instead of static numbers. I use TouchOSC on my smartphone to control it with when i practice. TouchOSC has a bunch of pre-made layouts, and the option to make your own too. Install the app on your iPad and you’re good to go. I did a write-up of my workflow here