What order to progress through Areas?

[WhiteFoxie]

Thanks to Gatts and Yenko, I now have pretty general understanding on how the difficulty progresses/changes in the game. So thanks guys.

Right now, i'm doing those crypt quests in the swamp. I think i'm level 8 or 9 (can't remember excacly), and I found the pirates on the eastern islands mostly slightly weaker. So I was wondering what I missed...

So I backtracked and right now i'm doing the swamp quests and it feels right on track. (I like to play safe.)
I have one question though. When you buy units... it shows what level they have.

Does that level stay like that? I have only seen (so far) one level 3 type of unit. Or will I find the same type of units later on in the game again, but higher in level?

And 50 level 3 archimages > 80 level 2 Swordsmen? (Do I need more of a lower level to balance it?)

Lovely game, can't wait till I get to play with some elves.