Selfishly - I'd much rather see a gigantic Busby Berkeley expansion (as they're doing with In the Heights) and sea battles and revolutionary war and cannons and whatnot.
I'm excited that more people will get to see the original musical of course - but the medium of film is better suited to immersive spectacle. I've seen Hamilton twice now at the theater and it's literally a work of genius, the best musical ever made IMO, but if anything the theater setting makes it feel contained and swollen - like it's on the precipice of exploding into real worlds and special effects and so on.
It's amazing to be in that theater, but being there is 80% of the feeling. It won't work as film as well.
Also, they filmed and captured the audio for this years ago and I'm not sure why what's effectively an editing job is going to take two years to make.
edit. Here's me at the Broadway show, with tickets picked up as last minute cancelations which is (usually but not guaranteed and you NEED a printer - digital tix don't work but kinkos or a hotel will hook you up) very easy to do. And look at these seats!!!!!