Make sure any mods you had installed previously are disabled. Some are causing this error, because most mods are not properly updated for the current game version (the guy handling them is working on it, but it will likely take a while). I know for certain the mod that adds extended relationships (grandparent/grandchild) breaks it.
Normally easy setup is as stated with fighters, or an early Necro that fills the other slots for you. I recently made Cali into a dodge tank with I think Ninja, the higher your MDef the more evasion you have. With high quality gear can hit 400 evasion and dodge practically everything. Game still needs to scale a bit better, I recommend doing fight content with like 2-4 jobs and not waiting until 5+ like I did. Every fight for me is pretty much a one shot and boring.
Try the Infinite dungeon. I haven't run through it but most people say if you want scaling then it's the place for it.
I usually run dark elf caster MC and Dragonkin fighter first servant. Dragonkin tanks, mage 1 turn wipes the battle. dont need more with the dungeon crew, later maybe become necromancer to fill in the team in fight, thou its useless since MC is fastest and kills everyone in 1 AOE spell, except some bosses.
itch.io has a later version that fixes many bugs including speed issues. There's still bugs but lot less.
To each their own. Personally I usually do 1 tank, 1 big melee dps, 1 rogue (front row)
