Typically 3 months of 500K+ embassy specific, that being said sometimes they ask for 6 months of bank statements to get an idea of your financial stability, but that doesn't mean the 500k has to be in for all 6 months.
I don't know what to say other than this must have something to do with an early check in time, for instance I don't think you're going to be let through passport control before midnight if you have a 4:00 a.m. flight. Regardless my understanding is it's always been the time you stamp out.
Typically hotels only copy the biodata page. This sounds like overkill. Certainly more than required for simply entering foreigner TM30 data online. Leasee doesn't have 3 eee's. Not from official government website.
Your history is quite typical, you shouldn't have any problems but then again nobody knows, have the three proofs ready, an onward ticket, booked accommodation, 20k baht.