Should I switch to a preamp with balanced outputs

Most great sounding pre amps do not even have Balanced connections. I'm not sure what the Question is? XLR connections are really meant for long cable runs, that's why its used in professional studio and stage environments. All balanced does is provide a third wire as a complete separate ground as well as providing 2 lanes for Positive and Negative to travel. Un balanced design is simpler and that's why many tube preamp designers avoid the more complex design of balanced. I have used both and I have heard no significant sonic benefit from one over the other. SO if you love the sound of your CJ ...I would KEEP it! at this point things get different not always better.

Years ago when I had a Threshold T2 preamp and a Threshold T400 amp, both had XLR and RCA outputs. I had two dealers willing send me VERY expensive cables of both types. I experimented with every cable until I was blue in the face.
In short, I could here no difference in the best RCA cables verses the inexpensive RCA cables. The Transparent Reference XLR cables made the biggest difference. Instruments had more air and separation around them. More meat on the bone too with deeper bass. I had settled on the transparent reference as the cables I thought I'd die with. After a divorce, I sold most of it to buy a house. I now see transparent selling cables for STUPID amounts of money. I'm using Transparent Super XL balanced these days. I do see that the older transparent cables hold their value rather well. If you can be happy with what you have, then good for you. Try not to let it drive you crazy. Good Luck. Joe

If your current combination sounds great to you, $700 certainly will not bring a huge benefit that you are seeking.
Just enjoy what you have, and don't worry about RCA/XLR.

Agreed, keep what you have!

Thanks for all of the replies! I think my question has been answered.