biggest thing about the firespray is that it's really difficult to play
large base with no native re-positioning and no 1-turn (dat table edge) makes the aux arc difficult to bring to play (all dem obstacles and ships), which imo means it's overpriced for its benefit
the difference of the aux arc on a small base v a large base (i.e 4 times smaller ) something you can't appreciate until you've played ARCs (or the SF)
Please explain, I'm genuinely confused by where you're getting that number from. Large base ships have a LARGER square area firing arc than small base ships.