A new year will make absolutely zero difference. I would say you will be allowed to enter providing you have no other history but will only be allowed a 7 day extension at most. Best to have a ticket out of Thailand, 20k baht in cash and accommodation booked. If you do have history in Thailand all bets are off
You each need your own money, your own paperwork, your own everything. There are a number of consulates that don't require the money to have been in the account for any particular length of time, even though they ask for 3 months of statements it's the closing balance of the 3rd month that's important
The money must be in a personal account. Money in a business account belongs to the business and not you personally. They want to see 3 months of bank statements but only the final month needs to have the 500k baht showing. The problem you have is waiting for the statement to show that which might be the end of the month if that's when your bank generates statements
My licence actually shows I have Category A which has no power output restrictions (rather than CC limits), I assume yours does too or you wouldn't get Category A on the IDP
Anonymous participant you mentioned earlier you didn't have an IDP which is frequently required. You also need a medical certificate from a clinic along with the residence certificate from immigration. Additionally some DLT offices want you to be on a Non-immigrant visa