Don't consider it the easy way out. Would you rather he struggle through school for the rest of his schooling (possibly leading to lack of interest ...)? Consider this decision for his COMPLETE benefit to be held back now - while he is young - in order to put him on par with his peers. He won't me MUCH more mature than his peers as he will likely be only a few months behind many of them! Since he has a summer b-day, he will be practically the same age ...
My brother was NOT ready for first grade (and our mom is a teacher) because it just wasn't his time to move forward. His b-day was about a month before the cut off and, in the end, he was with his correct peers (academically & emotionally) once he was held back. He thrived after the second year of kinder and was ready, willing, and excited about school after that time ... and he still had time to be a kid (playing, scouts, sports, etc.) instead of having to have hours of tutoring every single day ...
FYI, I also emailed this situation to my mom who is an early childhood teacher and she agreed that holding him back was the best thing they ever did. She commented that it was a very hard thing for her to do because she felt that somehow, his educational inadequacies were a reflection on their parenting. In hindsight, she knows that was not the truth (he was academically behind his peers and that stressed him out, too!).
Best wishes!!!