So God created us imperfect then holds us to an impossible standard and is punishing us for not living up to it? Doesn't sound very loving.

According to the religion, humans were created perfect and chose to sin. Everything since was an effort to redeem them.

If he had to do it this way because of his nature then he is not omnipotent.

Well yeah. Inherently. In fact, I think for any conception of a deity in a religious setting to make sense there must be some kind of limitations on that deity, whether understood by their worshippers or not.