Pattaya clear winner. Online dating (if you can call it that, rather finding a moneyboy) is so much more straightforward in Pattaya than in Bangkok.
For gogo bars, the choice is better in Bangkok, but prices are considerably higher, you would pay about twice as much as in Pattaya (drink + off fee + expected short time tip 200+400+1000 = 1600 for Pattaya vs. 400+600+2000 = 3000 Bangkok, my estimates/averages; I haven't been to a gogo bar in Bangkok for years because no value for money for me).
Level of English / character / shared interests for sightseeing, I would say it doesn't make a difference. But for attitude I would choose Pattaya, many gogo bars in Bangkok display their boys as "models".