Dollar Tree has had a lot of nice super hero figures recently in several different series.
This Spider-Man is perfect for 54mm.
Shown here with a Marx GI they look good together.
This other set has figures a little bigger, more 60mm, which is okay for me, because most of my figures are the larger size. Note the thick base also makes Batman seem larger.
Superman in a rather odd pose. I think since they are Super Heroes it's okay for them to be a little larger than life.
Aquaman and the Marx GI. Nice detail on the upper body and good value for a dollar.
The Flash, good action pose.
Wonder Woman, with her magic lasso. Her tiara is also a sort of boomerang with a sharp edge too.