you should never book a trip because of one or two events, especially one that hasn't even opened yet and is on hold indefinitely. At this point I don't think anyone who is booking trips hoping RoL is open can really blame Disney for it... it's a gamble that you take.
I can't afford to go so often anymore... so I picked december because of all of the holiday activities. Osborne lights is gone (I knew they would be but still sad about it), MSEP is gone (did not know it would be when I booked, still VERY sad about it)... but in general we are going for the christmas stuff and willing to go with the flow. Our last trip was over 2 years ago and our next one will probably be at least 4.... I'm assuming by then there will be tons of new stuff to see at the parks in 4 years, plus it will have been so long since our last trip everything old will be new again. If you have gone so much that you're only looking forward to one or two things that are new, maybe time to take a break and let all of the new stuff work its way out. There should be tons in a few years. Still I do get the disappointment (MSEP for me especially)...
But I honestly don't get what the big deal about RoL is. Anyone who is booking trips based on a guess at an opening date is doing so completely out of their own discretion and not out of anything Disney has promised at this point. I don't get a lot of the anger about it (not you specifically, just in general). I'm sure that every day it doesn't open is costing them money of sinking big $$ into this show and not being able to use it to keep people at the park and spending money later at night. I'm sure they want to open it as soon as they can. I just don't get why people are so upset about the whole thing. Sure, the people who booked based on the hype in the spring I get... Disney "promised" and didn't deliver... I don't have much hope for a first week of december show at this point and even if they have it, my plans are pretty solid. I am sure it will be there 4 years from now if it's worth seeing and if it's not, it's not worth seeing. Illuminations is my favorite nighttime show and we'll see that an extra night or two... it'll be 20 years old by the time we return and it may not be there so might as well get my fill of it now.