Can't comment on all of them but some I am a little familiar with.
Lake Region - This school has been a revolving door of head coaches. It appears that the current coach will be there for a second season. Maybe he gets things going for them.
Haines City - This school was one time really good. They won a state title in the 70's, went through a down turn in the 80's, returned to power in the 90's, then fell back off. The opening of Ridge Community High School hurt them some.
Estero - Another school that had a strong program in the 1990's - reached the state finals in 1998 and beat Lakeland along the way.
Southeast - Another former powerhouse hurt by a new school opening; Braden River, and lost a bunch of talent to Manatee in the 2013 season. This school was under a first year coach. They had a good team last year but had to forfeit several games. It wouldn't take much for them to get back to winning. They were district champs in 2015.
Mulberry - Like most small towns, they go in cycles. They are down right now, but every so often a group comes along and they will have a good year.
Tenoroc - Opened in 2008, had a decent year in either 2014 or 2015. Sandwiched between Auburndale, & Lake Gibson, two schools with a lot of tradition.
@OldSchoolLion - In past discussions of about bad teams, Bradenton Bayshore and Lake Placid use to come up but not anymore. Bayshore went 5-5 this past year; Lake Placid had a winning season and has made the playoffs 2 years in a row. What did they do to improve their situation that any of the other teams listed can't do? People are quick to say "lack of talent" but neither Bayshore or Lake Placid are hot beads of Division 1 talent, nor are either getting a lot of transfers in. In the case of teams like Southeast, or Bartow, I can say for a fact, the talent is there. Their linemen are big, their skill players are fast. Maybe they don't have excessive talent like some others, but "lack of talent" is becoming an excuse. Sorry to be blunt but it is. I might can accept the " lack of talent" reason for a small town program like Mulberry. While a new school opening may have an immediate impact, after a while that just don't hold it much more. I do believe that one issue is that when a program has a down year, administrators, boosters, etc, all want to get rid of a coach rather than stick it out. It also appears that some of these places are becoming "entry-level" coaching jobs.