This was always going to happen - some clubs would find summer wasn't for them and go back to winter. I've always said we'll probably end up with two similar sized leagues running consecutively, with a small overlap.
The main problem for most clubs in summer seems to be player numbers - summer holidays, music festival, weddings, etc on top of the usual work and other commitments have meant selection nightmares for a lot of teams. We're exactly the same, one week we have 40+ lads, the next we're down to the bare bones and a scratchy 17.
Still, for us summer is the way forward. Winter seasons were a struggle with facilities and poor numbers whereas we've got great facilities and strong numbers in the summer.