I need class help in Etrian Odyssey 2. I'm having a hard time with the FOEs on level 2, even with a party of all level 7-8 characters.
Class configuration depends a lot on the floor you're on and how your playstyle is built. My party when I started the game was Protector - Warmagus - Troubadour / Gunner - Survivalist. My current primary party that I'd been using since the 3rd strata is Warmagus - Troubadour / Gunner - Hexer - Gunner.
The important points in party construction are survivability and synergy.
Survivability consists of not dying. This first usually means having a good healer - you pick from Medic, Warmagus, or Beast. While it's doable to run about without a dedicated healer and rely on items, this is better done in the late-game when you've setup the other points. The second part of survivability is strong meatshields in the front. To your benefit, properly built Medics, Warmagi, and Beasts also serve as strong meatshields, so you can opt to only have one or two front-line warrior types if that's your style. Protectors and Landsknechts make the hardiest of front-liners, but Ronin, Darkhunters, and Troubadours also work well. The final point is obviously speed in your offense. Dead enemies are no threat, and this is what makes healer-less parties viable are teams who can kill the enemy quickly without sustaining too much damage. Disabling and crowd control, as discussed later, help a lot in survivability.
Synergy is making sure your party works together. The obvious part of this is classes that have skills that work well off of each other. Landsknechts work great alongside Ronin, Gunners, and Alchemists for the elemental chasers skills. Warmagi and Hexers have huge skill interdependencies that can actually itemless self-sustain the whole party's HP and TP if no one dies. Troubadours work great along everyone by buffing stats. But the second part of synergy is making sure there isn't huge conflict. If everyone is all using swords, then you're quite doomed when the enemy is resistant to Cut damage. Too many healers means a very weak offense. Because buffs have a limit of 3 per character, make sure Troubadours aren't overriding their own buffs or the self-applied buffs of other characters. And don't forget to pay attention to synergy between everyone's force abilities! Survivalists are poorly matched with Troubadours thanks to this!
Some other focus points to consider are crowd control and disabling. A party that is focused entirely on singular targets can easily meet its ruin against very difficult enemy groups, so having one or two characters who can attack multiple enemies is very useful, even if it is only with the force ability. Disabling comes primarily from the Hexer and Darkhunter's abilities to cause binding and status ailments, but Survivalists and Gunners can make due with Number and Riot Gun. While disabling is not necessary, always consider that disabling the enemy for a few rounds can give you a more than welcome opening to heal or kill. So it is also convenient to have.
A lot of this strategy will also change based on what you are fighting. The important thing to understand is not just how to maximize the potential of one party of characters, but also how to setup several sets of characters that can be safely swapped for the right situations. Swap in the damage types you need, swap out disablers when it's less necessary, similar actions. Remember, survivability and synergy are the key points! Get those down pat and you can construct wildly unusual teams like 5 Ronin!
But Shepherdess brings up an important point - any party is weak if you're too low of a level. Always address how well you fared against a particular FOE if you get slaughtered. If you were, in fact, slaughtered, then it may be taxing but levelling is really the best idea. Consider training with a Troubadour if you're finding it taking too long - they have a passive skill that increases experience gain for the whole party.
The party I was playing was: two melee characters in the front row, one spellcaster, one healer and one ranged at the back row. It worked well for me. Bear in mind that this game is quite difficult at first levels regardless of the classes you pick. If you can't kill FOE now, level up and come back later.