I loved Groundhog Day and it seems likely that it won't last much longer, so this would be my first choice.
I enjoyed Come From Away even more than Groundhog Day, but it will likely be around for a while longer and may also tour. The only caveat to this one is you'd be seeing the original cast, which is brilliant.
Miss Saigon is set to close by the end of the year and the current cast is mostly quite good. It's a spectacular production with a heart-wrenching story and I believe it will also tour, but the quality of the touring cast is an unknown at this time.
I've not seen Bandstand because the swing genre is not really my cup of tea. However, a fair number of folks on this board love it, so much so that I'm considering checking it out anyway.
Wicked isn't going anywhere anytime soon. It will being playing in New York (and likely London as well) for years to come, and it also tours often. I saw the London production several years ago and thought it was wonderful, but I'd put it at the bottom of the list because there's definitely no urgency here.
==> this board is a nest of vipers <==
"Michael Riedel...The Perez Hilton of the New York Theatre scene"
- Craig Hepworth, What's On Stage