An 8'4 bic is a great board to start on
... very stable, easy boards, and you obviously feel ready to progress on, but i'd just be a little careful about going too small too soon, as it can really hinder your progression, and its a mistake many of us have made in our first years of surfing
I mean its hard to give advice as to particular boards without knowing someone's level, but, but My personal opinion (and its only my opinion!
) is jumping down to a 7'2 super fish is a very big drop in size, that may prove a little too much. the difference in stability, and paddleability will be huge
those bics are so fat and floaty, and stiff and slow, which makes them great incredibly easy to ride, beginners boards...So the thing is you wouldnt necessarily need to drop length much or if atall,( in fact you could even go longer).., and still have a board thats much faster in the water,and far more manuverable than what you have now, but is also still nice and easy to paddle.....that way you keep your wave count up, and get to progress on quickly with your turns etc.
think of your next board as a stepping stone to the next one. buying second hand is a option worth considering, as you arnt continualy loosing money on brand new ones! I'd recommend something like either an 8 to an 8 and a half foot mal, or even better ,a large (7'10 ish? ) magic carpet type of board with plenty of volume and width. will go like s**t off a shovel compared to your bic!