Much better than all the anxiety of travelling from the city. In most Western cities, those airports hotels are a swingeing premium price. But BKK has room available with a shuttle, for 1,000 baht or less. And if you wanted, you can use the Skytain to get out there the evening before
You would enjoy Cambodia and Vietnam. Its pretty cool to travel by bus between them. Cheap and comfortable. Takes a while but you get to see more. Always a tuktuk to take you to a hotel at the bus station
Two major roads run through Pitchit going North/South. Road 11 on the East side and 117 on the West. Get a lift to any modest size town on one of those roads. You will for aure get a van/bus to Bangkok at the city of Nakhon Sawan
I read the other comments. I agreed with some and I disagreed with some. At least they added to the sum of knowledge. You added Fk@ll I suspect that's your whole life story
The agent uses your bank account. You attend the bank with them, and a few other clients. The agent works with one of the tellers to deposit the funds in each client's account in turn. Once the agent has a statement showing the deposit in your account, the money is moved to the next client's account. You come away with a credit and a debit, a couple of minutes apart