We ate breakfast there with our 3 year old daughter. Honestly, once is enough. Especially since the castle is undergoing renovations, we would not waste the money.
We saw Cindy in lobby, Aurora, Snow White, Ariel (green dress), and Belle in her blue dress. Character interaction was mediocre. They come, do their job, go on...
If you want Belle in her yellow dress, head on over to Epcot to Akershus (Norway). The character interaction IMHO has ALWAYS outshined the experience at other character interactions (except where Pluto spent 30 minutes with us the Swan). Personally, I think the food (breakfast, lunch, and dinner) is superior at Akershus. At Akershus, we have seen Cinderella, Jasmine, Snow White, Ariel, Belle, & Aurora. We once saw Mulan through the window.
Tiana is available to see in her Garden which is across the bridge in MK, behind the XMas shop. I think she (and Prince Naveen) are the most personable, talkative, and interactive... but then again, she is my daughters FAVORITE!
We head to Disney every 4-6 weeks since my husband is contracted out with them. We just completed our 9th trip since May and I can honestly say that we have eaten in EVERY restaurant. Cindy's for us was a "one and done".
I hope you enjoy your Adult only trip and have a great meal at the castle!