Are these character sprites too big for a 16 bit Mario fan game?

[HellJumper]

If so, then I will design the levels around their size, but do you think I should just start from scratch and make new sprites for the characters? I mean, the sprites I have here are more accurate to their actual designs than really any custom sprite style that Mario has been drawn in, where his body is the same height as his head, or something like that. I'm kinda going for a more real modern look with these, which is why they appear bigger. And if there is a gap that is 2 tiles large that the characters must get through, then that's what their crouch walk animations will be for. But what do you guys think? Because I'm not sure I can confidently make these characters with their modern designs in such small space to do so.