I've done the Rose & Crown for the last 2 year's CP and have been very pleased. I've dined at Le Cellier and have also been pleased.
When I went last year, it happened to rain 1/2 way through the performance. I wanted to sit under the overhang, but the CM kept telling me I'd be much happier further back. Well, sitting in front of a walkway with people constantly walking by and being beyond the overhang damped things a bit. Also, it was still a bit bright out, so you lost a little of the candles, lights, etc. To finish off the night, I was outside for dinner, wet, cold & tired and just did not feel like wating around another hour for Illuminations to start (early PS). I would recommend the 2nd show of the night and sit under the overhang.
If you do the 2nd show, ask for a PS after that at the Rose & Crown. When you check in, request a patio table. This way you can enjoy a great meal, then sit back and watch Illuminations from the comfort of your table while enjoying dessert.