I have a few favorite combinations. I like to try and achieve the "special snowflake" party layouts, so I'm always experimenting. For me, party creation is half the game! I am known to have spent several hours just creating parties, then scrapping them and starting all over again
My favorites:
Lizardman Barbarian
I really love Lizardmen, With 2 additional Dex, and 10 Str / Vit, they work well in any role. And the elemental resistance they get is amazing through the entire game
As a front-row fighter, go for Fast Metabolism and Healthy, skill into Heavy Weapons and Accuracy, then put all your attribute points into Strength and Vitality. Very high health (and regeneration), hard hitter with a heavy weapon in hand and with good hit chance, strong resistances, this is a very durable fighter. To top it off, health potions are twice as effective (because of Metabolism trait) !
Insectoid Knight
With Chitin Armor trait, and 4/5 Armor spec. This guy goes for heavy armor sets. With very high protection stat, extra evasion from Knight bonus, and 50% injury reduction, this is a very enduring front-row fighter. Give him Heavy Weapons skill and he can also dish out some real damage. Insectoids are a bit underrated, they are the next strongest race after minotaurs, and the injury reduction is incredible, even if you rarely think about it. If you pick the "Quick" trait and skill 3 points into Dodge, you will hit very fast!
Lizardman Wizard
The famous lizard-wizard. With Fast Metabolism and Endure Elements traits, and going for the Archmage clothes, this guy will have insane energy regeneration, and will be almost immune to elemental damage!
Minotaur Alchemist OR Rogue
This guy skills into Alchemy and Throwing. Give him Endurance and Head Hunter traits. He will have insane carrying capacity, he can carry the items for your entire party! He also dishes out heavy damage, because throwing is Strength-based, and to top it off he mixes some crazy potions. There is an abundance of throwing items from the very start of the game, so this guy pulls his load, quite literally
He can be either Rogue or Alchemist. Go Rogue if you want to hit harder with those throwing axes in the late-game, or go Alchemist if you want to create more potions.
Insectoid Battle Mage
This as another solid front-row fighter, for much the same reasons as the Insect knight, however as a Battle mage, with a staff in hand plus the protection spell, this guy gets a whopping +35 protection stat! Add to that the Chitin Armor trait and you have 45 protection before you even leave Twigroot Forest. Impressive! However, he is lacking in offensive power, he tries to be both a Wizard and a Barbarian, but ends up somewhere in between, with low physical damage and low energy pool. I don't recommend this combination
Lizardman Rogue
-Very- solid backrow character. Give him the Poison Immunity trait, and skill into Missile Weapons + Critical. When you get him some arrows and a good bow, he will be an amazing damage dealer for your team. And with the high dexterity, he tends to avoid taking damage at all. Very sneaky and strong character. However, i don't recommend him! Why not? Because you're better off bringing an alchemist (see my minotaur alchemist combo above). The thrower can deal very comparable damage to the missile shooter.
And now, for the characters that i don't like: (spoilered because lots of text!)
Ratlings
So the ratlings get +15 max load. BUT they also get -4 to Strength. The weakest race in game, they actually have the same carrying capacity as Insectoids (who have 5 more Strength!). With most weapons being based from Strength, a ratling makes for a poor front-row fighter. But oh, they have +4 Evasion, right? Well no, they only have 2 more evasion than the Lizardmen. And compare +25 to all resists, to the ratlings (VERY situational) disease resistance. Lizardmen wins every time. Basically, if you want a Dex based character - take a Lizardman. Want a strength based character - bring a Minotaur. The ratling has no place in the party.
The Mutation trait is also very disappointing, because of its random nature. The only reason i can see to bring a ratling is if you want to feed him a lot of cheese

There's tons of cheese in the game, so with some luck you can get his stats up i guess.
Fighter
This class is just a weak barbarian! I have played through the game many times, but i have never once brought a Fighter. His Health scaling is awful compared to the Barb, but they have the same Energy scaling. And the Barb gets +1 Strength per level! Which equates to carriyng capacity as well as damage. The Fighter is just a very poor choice to bring along because of this. Wanna use a melee weapons special ability? Bring a Battle mage instead! Or heck, just use your barb! Just spec a few points into Concentration, and with that extra Strength, you will do way more damage than a Fighter ever will.
Dual Wielding character / Light Weapons character / Backstabber
Oh god, please don't even try. I've watched many streams / playthroughs of people picking a Light Weapons specialized, Dual Wielding character for their front-row. This is just such a bad choice! It's so bad, i'm gonna name five reasons explaining why:
---1. The Damage is lower than for Heavy Weapons
Because of the way Protection works in this game, a hard hitting weapon is preferable. With fast light weapons, if you hit a well-armored target such as a crab for example, your hits will often only do 1 damage. But if a strong minotaur with a two-hander hits that same crab, he will hit for 40! Why? Because the crabs protection value shaves off a certain amount of damage from each hit.
---2. You must click more to achieve the same DPS as a Heavy Weapons character
With a dual-wielding character with fast weapons, you may have to click as often as once every second, just to achieve constant damage-dealing! The heavy two-hander warrior next to you is clicking once every 6 seconds, and achieving the same DPS.
---3. Achieving a Backstab is very difficult and a rare opportunity
You probably looked at the Critical skill, and noticed the 5-point bonus. "Wow, i can backstab crit for triple damage with any light weapon? I will be one-hitting monsters!" Okay, to get a backstab the monster has to be facing away from you. The problem is that -every- monster is programmed to turn
towards you. You will never get a backstab in the narrow corridors of the dungeons! You can try combo-ing this with Frostbolts and Invisibility, it just isn't feasible. Sorry
---4. The access to Light Weapons is much worse than for Heavy Weapons
You just don't find as many cool Light weapons as the Heavy ones. That's how the developers decided to do it.
---5. The Rogue is
AWFUL in the front row!
A dual-wielding Rogue in the front row? Recipe for disaster. The Rogue's health scaling is awful, and his survivability compared to a Knight or Barbarian is bottom-tier. "Dual wielding rogue in the backrow, maybe?" you think. Well at that point, you might as well make him a Missile / Throwing Rogue. For a backrow-melee-character, a Heavy Weapons Barbarian is a much better choice, for the above reasons.
I think i might have been carried away here, but that just shows how much i love this game

Can't wait for a sequel / expansion, seriously.