we're running thief, archer, cleric, sorc. It's a bit of a slog at the early levels, but we're kicking butt, rather than the reverse, in the 20s.

The good news is that once you hit 10-ish a lot of lands are survivable.

Hints:
Peter's suggestions are excellent. Prioritize the sorc promotion (Bracada).

Go to any land except Nighon. They should all be survivable. One part of Avlee you'll want to avoid; you can tell it by the insane number of water spells thrown at you. Take your time in Tatalia; 'tis better to hit than to be hit.

Make sure all of your party has the bow skill and a bow (even though the sorc stinks at it).

Visit every building in the towns to see if there are quests. Peter gave you the promo quest locations but there are also side quests that are looty and fun.

Always use Wizard's Eye.

I strongly suggest getting Remove Curse before tackling Deyja. Erathia has the guild for this spell (or just have a lot of potions on hand, but eh...inventory space!) If you need money, Deyja's a good place to loot up. By contrast, Bracada is tougher if you're poor.

Since you have a sorcerer, use Fire Aura to add damage to all weapons plus the Bless spell from your cleric so your kids can find the broad side of a barn, and the Heroism spell, too. Don't disregard the archer's ability to spell cast; it can be v. useful in a tight spot.

Use any pedestal you find. Wells are usually beneficial but sometimes are not (it's worth the risk!).

Party planning: Use the manual's charts to help you decide the best way to specialize your characters, and play to their strengths. Not everyone needs ID monster or repair item, for example.

Turn-based mode is easier for fighting.

Invite a friend over to switch off clearing Avlee, Bracada and Deyja. They can get tedious.