@inception
TL;DR: Had I been given the choice, I still would be choosing Michigan over Cornell here at the masters level based on funding and future planning.
First, congratulations on Cornell! I didn't get in (although I had a nice email from the department). Michigan has been my first choice throughout the whole process, so I wasn't heartbroken over the rejection. I'd thought the same things about Cornell just the night before...no funding other than FLAS, which still left a deficit. I'm pretty sure there are no TAs available at the masters level, but I might have read that wrong.
Also, the Cornell Asian Studies MA track doesn't have the review to continue on to PhD (like the Asian Literature, Religion, and Culture MA). Professors that I want to work with at both Michigan and Wisconsin have their PhDs from Cornell so in my long term planning for a future PhD, I could earn some very nice recommendations for a future application there.
For me, had I gotten Cornell, it was easier to consider relocating there than it likely is for you. Both Cornell and UM are about six hours from me. In fact, I didn't apply to either UHM or the University of Washington in consideration of relocation costs and distance from home. If family and returning home for visits to Arizona is important to you, I'd look into what that would cost from each place. I already live in a climate where I'm used to wintery conditions, but you'd want to factor in the cost of winter gear and weatherizing your car to live in Ithaca. I'd also try and determine if it is feasible to leave your car rather than transport it if you go to UHW.
As far as funding at UHM, you could ask for in-state tuition if the yearly cost exceeds the 18K (I think) from FLAS. Plus, as you said you have some other funding options that might work out.
Good luck! Cambodia is a both beautiful and haunting given the history of the Khmer Rouge. It's a fascinating topic. Feel free to PM me also to further discuss any of this.
PS: I didn't get FLAS at Wisconsin, so will be declining there. Still waiting on final funding from Michigan but it looks much more promising between FLAS and a fellowship the review committee nominated me for.