Interesting question MP... not one to answer straightaway! But if you look at the Rolling Stones (something I try to avoid these days!), Deep Purple, and a lot of other bands who mainly remained the same after one member left, then reluctantly I'd have to say yes. With the exception of course of Queen and INXS, I find that really embarassing and I'd never go to see any of them.
But especially with the line-up you are suggesting, with Nick and Mark, and who knows, maybe even Tim!I think that would be Crowded House alright... And I'd go to see them as well! Of course I would. But still, it's not the same without Hessie, and I'd hate for them to call it a reunion. That most definitely wouldn't feel right. It's simply not a reunion without him, in my opinion.