Advice on Logistics

[goji]

BUT I'm arriving at BKK at about 5pm along with about 15-20 other international flights, so I anticipate a long wait through immigration. Not sure if I want to wait for a bus at that point and if there is already a line, possibility of waiting another hour for next bus.

This is easy.
Arrive 17:00
Immigration + bag collection -18:00
Wait for bus ~1 hour
Bus to Pattaya & transfer to hotel ~20:30

No time to check in, shower & chill out before heading out to the gogo bars. So prebook a taxi. Maybe: www.thelimopattaya.com