You shouldn't need to go to the immigration office. The TM30 can be filed online very easily. Whoever owns where you are living or staying should be able to either use their existing online account or register for one. Then TM30 can be filed in a couple of minutes.
Malaysia is the absolute worst option in SE Asia if you want to get a Thai visa. They are very slow, very demanding, request things many of the other Thai embassies do not request, and request documents you already sent them multiple times. It can take more than a month sometimes, and you must remain in Malaysia the entire time. Even going to Yangon Myanmar is a better option than Malaysia.
Bring proof of your flight out and they might accommodate you. But beware, the reason many under consideration stamps are given is because your immigration office cannot process the extension and has to send it to the district office. They probably cannot rush that process. So worst case scenario, if they say they cannot do it earlier, ask them if they can do it later. Your under consideration stamp is considered your extension time already, so you should be able to get a re-entry permit and leave and return while under consideration.
Haven't read that anywhere. It's that they're going to stop accepting IDP to let you skip the written test for the first license. Renewals shouldn't change.
Medical certificate is for non-OA not non-O. Are you are you applied for the correct visa?
But aside from that, Malaysia is known as one of the most difficult places to get a Thai visa in SE Asia. They ask for extra documents, sometimes many times for the same document.
Every page of passport is a common request to make sure you're in Malaysia and never left. Sometimes they can take over a month too.