I use a wide gap in a size 3/0. Some might say that a 3/0 is too small, but I find that I get more hook-ups with this size than with any other size.
I slao started to try circle hooks this past year. I used a size 6/0 Gamakatsu octopus circle. It worked fairly well, and I'm going to try experimenting more with circle hooks this year.
If you try circle hooks, be aware that different manufacturers use different numbers for their sizes. For instance, a size 6/0 gamakatsu is not the same size as a 6/0 mustad, and so on.
I started using Owner Mutu Lt Circle size 3/0 and 2/0 last year. While the hook may seem small, I had no problem catching fluke up to 7lbs. I practically eliminated getting gut-hooked fish. 98% of the time it was wedged in the corner of their jaw or impaled into the lower jaw. This will now be my go-to fluke hook this upcoming season.