Thanks everyone. So basically, larger maps = smaller fleet size.
I've never come close to using all 16 in multiplayer. The most I've ever used at once is about 10.
I cant imagine using all 16 in Multi. However, once a friend and i were 2v2v2 against 4 A.I. I was testing the position of Eco., and at the end when i had 400 000 + credits in the bank with everything researched, i decided "Well, since we've already won..." scrapped 4 trade ports for 4 Cap ship factories, and built 16 Marzas (silly Akkan was destroyed due to negligence on my part a while back...)
Yeah... 16 Marzas using raze planet was... epic...