The most efficient party: no rest, sleep, extra food expenditure, HP and PP potions

[UjinK]

Cleric Barbarian Barbarian --
Thief Paladin Gaulen --

Cleric - Febret, Fast Reflexes
Barbarians - Febret, Axes, Fast Reflexes
Thief - Velvet, Crossbows, Lockpicking, Trap Disarming, Shurikens
Paladin - Taliet, Polearms, Perception
Gaulen - Knowledge of Herbs, Knowledge of Terrains, Mercantilism, Object Identification (CON + SPD, 3-5 Armors)

Yeah, that's pretty much how it works

But not for ironman, that's clear

[Radagast the Brown]

The classes you are using are all pretty great, but this doesn't seem optimal. There is no world in which putting the paladin in the backline instead of the frontline and the cleric in frontline instead of backline, where this is optimum compared to the exact opposite. The cleric is made to be a backline pure caster, while the paladin is made to be the perfect middle position tank. Switch those positions and you will indeed have a very powerful combination.

The cleric does not really have the skill points to support melee skills (3 points each is terrible and no weapon skill attacks). He is made to be a caster. His armor skill is super expensive as well (3). At the same time the paladin does get the divine prayer, which is all he will ever need to support his skill attacks with PP and take advantage of the frontline with his strength and armor. He raises STR/AGI/SPEED, so he is perfect in front unlike the Cleric which might get health, but not other stats and armor to better support the front position.

To add even further to making an invincible frontline though, there is also another strategy, going for full evasion with the frontliners (evasion God too), fast reflexes, having the paladin max aura of protection as fast as possible while ALSO having a bard in the backline for even more extra party evasion. This is sort of a niche build, but is in fact the best way to ever truly utilize the evasion stat in this game and makes for an incredibly easier mid and endgame though it does have quite a slow start.

And to cheat the game even further you could even put 2 paladins in the party, simply because their aura does stack upon each other. That's not necessary though. (so both bard and paladin can serve the same purpose after the first paladin, so I tend to prefer the bard due to other perks) Keep in mind that this is how the evasion works to stay relevant all to the endgame. Its an all-or-nothing thing. If you don't do all of that, the evasion will simply not be good enough at some point. And in that case, immunity will in fact be better than fast reflexes.

Constitution is mentioned in many guides, but it is severely overrated and way less useful in a party with an aura paladin and evasion/fast reflex shenanigans. It doesn't make you stronger like other stats do. Its best utility is in fact the ability to carry more stuff in backpack. In a balanced party you practically never need extra CON on the frontliners if you know how to build them, and the backliners just need "some points at beginning" and then they are good for life. Its definitely a noob stat for such parties. Characters are in fact better off doing things with other stats most of the time even if its just agility and strength for that odd bow user. (speed is a given, so we are talking about the other stats here)

Potions are not really needed after the early game, however they are a convenience to save some time by spending gold.

Gaulen seems like a failure to many people, but if he is put in the back with a bow, and focus him just on STR/AGI/SPE , herbs/terrain and absolutely nothing else, it means he can become an insane bowman with envenom strike. (Armor is useless on backliners.) The only way to do that properly is to have other classes take the burden of literally ALL other misc skills. Which is very possible if you have a bard and a thief for instance. Hence these classes are in my opinion the saving grace of Gaulen, letting him be the great archer he was always meant to be. Ofc he can pump immunity/reflexes later on. This is by far the best way to build Gaulen.

[EolSunder]

well you can build Gaulen either way, front line tank or back line archer. Either way he isn't going to be a useful fighting character until level 30+ once he gets some of his misc skills maxed out. You can keep him up front with max speed/con with some strength for extra armor to absorb hits, or safely in the back if your using extra front liners. But until he actually gets some combat ability he's usually just attacking who ever is currently stunned or frozen so he can actually hit stuff. Same with any non-front line warriors. I always use him as a tank up front while my cleric, mage and bard are in the back on support. But if you don't use a mage, bard etc he can kick back in the rear row and later can actually function after level 30+.

But for his party, yes i also would put the Paladin up front and the Cleric safer in the back to buff and heal the party, and once in a while with a pole weapon to contribute stuns if he doesn't need to cast. Late game the cleric really is just a divine spell caster to help wear down all those demons you will face.

[UjinK]

If put paladin in front, he has to be in the middle and one of the barbarians ends up on the edge, which is bad

[Alakhai]

2 barbars with axes, gaulen axe too, 3 priests, no need to rest at all, i am at lvl 21 hardcore ironman, and i am at day 37