RE: evo - is anybody there?
Its hard to say which fin size that is the bggest (depens a lot on fin type too). 28cm sounds kind of big though. Is that a 28cm wave fin? Is it stiff or soft? The 24, is that the original black Drake 24cm (very flexy and swept back)?
I personally don't think fin size is what limits you so much here, but for B&J sailing you could of course try to go even bigger. Some people have an easier time coming to grips with sailing the EVOs effectively when raising the boom a bit. Some also get a better feel for the board when moving the straps a bit forwards. EVOs also take quite well to a fairly powered up sail, so maybe you could try to hold on to your bigger sail a bit longer. Note that the fin size is kind of dependent of riding speed, so it might be good to use a smaller fin when you sail more overpowered, but this is also very much a question of technique and style.
Which sail sizes do you have for the E92?