There is that. Mike Moran is definitely what you'd call 'good-hearted', if not very effectual.

The problem is that Miracleman isn't quite Mike Moran in the same way that Clark Kent is Superman. The Miracleman body retains traces of its' own instincts and behaviours. It's colder than Moran in some ways. Less squeamish and more amoral.

I think that's obvious toward the end when Miracleman goes to Liz and offers her a superhuman body. It never occurs to hm that she still identifies him as her husband and that only a short while before he'd had sex with Miraclewoman above London and in full view of the public (who actually applauded!).

Mike Moran would have understood why she threw him out, but Miracleman didn't get it. For that matter, neither did Aza Chorn, showing that Miracleman by then had more in common with the alien Warpsmith than with humans.

There is almost never any trace of Supermans' Kryptonian heritage n the character except for his physical abilities and weaknesses. Most of the time, he's just a big, easy-going Kansas farmboy. Clark Kent, not Kal-El.