Thanks for playing and for the feedback!
Definitely agree with you on the size thing, especially since some fishes are naturally smaller than others.
Had some ideas to make things clearer but nothing was satisfying enough for me so I just let things like that.
Regarding more smaller fishes at first, there is a difficulty that increases over time but since there is a random part, you might still get too much big fishes at first (it was even worse before, it's one of the thing I tried to adjust at the end).