At your son's current age my son moved to a Team 2 from a long time team that was run by dad coaches. Like you had the same level of success. Quite simply they had lots of good players.
Two years now in the rear view mirror and from a parent's perspective really glad we made the switch. My son had to learn how to play on a team where a dad wasn't making the lineup. Performance, attitude and hard work mattered and how you got in the lineup or came out of the lineup.
In looking at it another thing that happened that at the time I could not have anticipated as I was "in the moment" was the majority of boys that were on that first very succesful team haven't had the same level of success as my son and a few others. For lots of reason and most not due to their ability. They gravitated to another sport or interest in a lot of cases. Kids and their interests change.
Good luck to your son whatever way you choose.