King's Bounty: Armored Princess

/// about the islands, which is better to clear first, Bolo or Crimson Wind?

It's better to start by clearing Crimson Wind!
But, personally, I always leave 2 neutral squads on the island untouched - one, near the Coastal Church, a little lower (as you go down the wooden deck)... they guard a scroll and a chest. And the second - the quest hero Hector Norb.
I do this because I'll return to the island a little later.

This is my third playthrough, and I've realized that it's better to do it this way.
Debir, Crimson Wind, Bolo, Rusty Anchor.
At Rusty Anchor, we learn the password (Squid) from the parrot to enter the cave on Crimson Wind (the cave is called - Strange Door). And until you visit Rusty Anchor, you won't know the password - you won't be able to enter the cave - Rob Squid's Hideout - right away. And the cave is very good; after the battle with the zombie hero, there are always very good artifacts in a couple of chests!!!
Therefore, after Rusty Anchor, I sail to the 1st island - Debir, where I exchange the amulet of azazel (from the island of Bolo) with the priestess for the Stone of Hope!
After that, you can buy some valuable, expensive artifact from the King (you already have a lot of money) and sail to the 2nd island - to finish off one neutral squad and Hector....plus the Squid's cave.
Then - to Verona!!!

P.S. - you can also do this. After Rusty Anchor, complete the quest - mercenaries for Sohat - bring him 50 each - bandits, archers, pirates (this is already a matter of chance). For this, he gives you a key to enter the orc cave here on the island. Before entering, the quest hero Zag-Zag stands guard. In the cave, the Emerald Dragon (1 unit) always joins! It can be very useful to have one dragon in your army at the beginning of the game.
But I haven't completed this quest for Sohat yet - I'm too lazy to waste time swimming back and forth, buying 150 extra soldiers.....

Added after 2 hours 38 minutes
I only just noticed that on the second island - Crimson Wind, you can get a useful artifact - shark tooth! (+5% experience and gold per battle) as a gift in a conversation with Jimmy Crowd (whom you can take as a companion if you wish) if you build the dialogue correctly at the beginning:
- it's not what's on the outside that matters, but what's on the inside......
- you saved a girl from a shark, amazing!......
get the artifact!!!!

P.S. - I cleared 4 islands, and only now did I discover this :(