Okay, so it's day 10 already because of my travel between islands, and I am up to 102 fights without loss. I found the Portrait of the Griffin which means I can use Red Dragons and Griffins without less than neutral morale. So the Royal Thorns are in reserve - they're just too difficult to use with no losses.
I beat Zig Zag on Rusty Anchor but I can't seem to work out how to get into his cave. There's just one map guardian left there, and the other three small islands are all clear. I think I am almost level 20, about 7000 leadership. In Verona, I've managed to take out about two thirds of the stacks, but I've left the most difficult ones for now. (including heroes like Halt and Peter Drayan) The easily stacks currently are on Montero, some of which seem very easy. I can probably find another 10 or so easy fights on Montero, which means probably 2 more levels.
Attack is about 16, Defense 22, and Intellect 5. I am giving up on Intellect really, as I don't plan to use direct damage spells at all for the whole game.
Things are going okay (surprisingly smoothly this evening) but I am lacking some things that I expect I'll need:
Target spell (not in Verona)
Time Back spell (likewise)
Archmages (only 4 of them - none in Verona)
Resurrection spell (haven't seen it)
Presumably all of these will be available somewhere, hopefully in Montero.