Couple of issues..
I think Melissa Benoist is too "Old" to play super girl.. she has just a tad too many wrinkles vs the comic book feel..
Not saying she's ugly or anything, just the age seems off..
I'm not talking about super girl's age in the comic, rather her appearance..
Because, for the most part, the acting still depicts a Younger girl with a sense of naivety. Yet Melissa Benoist physically looks almost 30, well beyond the point to behave like that.
Costume.. those weird looking boots look really weird..
I get that cartoon super girl has impossibly leggy-proportions, but just give her normal stiletto boots, The modern audience can accept it just fine, but those current weird boots... just look so weird..
Also, again.. her proportions.. they really needed someone either more buxom OR with a much thinner waist to capture that comic book look..