I live in the Eastern Seaboard, but I would never call this "Pattaya area" as no local Thai would ever call it...Pattaya is a pretty small area in comparison to the whole Eastern seaboard, which includes the provinces Chonburi, Chachoengsao and Rayong (of course most foreign tourists and expats are in Pattaya rather than other parts of this area)

as i live in the northern part of Chonburi province, Suvarnaphumi airport is not much more far away than Utapao airport, so I do not see any reason I would use it.
As far ase I know, there are many more flights during high season; also international to Russia, China, Malaysia, Singapore. I think even one of the large middle eastern airlines considered flights to/from Utapao