My budget is $4500. I am slightly flexible, but have roughly this amount for a 70" flat panel. I don't need 3D, but wouldn't object to it either. I really want great picture quality, and don't care about apps, smart tv, etc, sound....just picture quality, and 70". Currently I have a 55" Samsung series 6 (or so I believe, since I'm at work I can't verify this). So this being my requirement, what would you purchase if you were in my shoes?
I failed to mention a few things. If I were buying a new TV, I would pull the trigger on an Elite 70" if you can still get one. Don't wait as supplies are disappearing. Assuming you can get one for $4500, I would add on a few years of Best Buy protection. Between this and tax, you should be just north of $5k. Sign up for reward zone for a lot of free BB gift cards and a 45 day return policy. Best Buy has 24 month 0% financing, which I would enroll in and put down about $3500-$4000. (The monthly payment would be stupid low). With the leftover cash I would get a PRO calibrator on tour to come over make it damn near perfect. This will meet all your criteria while giving you arguably the best TV ever.
If you can't find an Elite you may be able to make up for it with a Sharp 80" 632 series as it's one of the highest rated and perhaps you can get more Wow and I've seen it for a grand less than your budget this past week on the Big River. Another option with best of class PQ would be the 65" Sony 950 series.
+1 for what has already been said here. 70" Elite leftover or new 80" Sharp as a backup plan, if space permits. I think the 2013 80" Sharp will be significantly improved, and might be a great size/PQ combo for the money.