Youth sports have not only become more and more competitive, they sometimes force specialization. Remember, on any youth sports team you will have a mix of players with different strengths and levels of abilities.
Here's what the coaches assess immediately: speed at very short distances (20 yards), ability to catch a football, arm strength and accuracy for throwing, blocking ability, aggressiveness, agility and ability to kick the football. They will be observing, measuring and then ranking the players. The coaches are already narrowing down players into positions and starting time. Play to this mindset.
It's unrealistic to pretend that every player is equal in ability and potential at a certain position. Not everyone can start. Not everyone will have equal playing time. What is realistic is to seek out those coaches who know how to include all players and encourage incremental improvements.
Your child will benefit the most when the coach knows how to insert a smaller or less talented player into a group of larger, more experienced players, one play at a time. This rarely penalizes the team on the field and gives the inexperienced player confidence. Players who have small roles but are not discouraged during the first year, have a better chance to improve, mature and contribute more fully the next season.