Going below the standard 5 man parties

[Cross The Rubicon]

I remember in my play though of EO3 that having smaller parties was feasible, especially with ninjas, but in EO4, such slot filling skills are gone, are 5 man parties absolutely mandatory now for a play through from start to finish or can smaller parties work with a little extra grinding?

[Garlyle]

Well, I'm going to be finding out since my NG+ run I'm starting now is a party of nothing but three dancers.

I know the game definitely is designed in such a way it expects a more varied party composition in terms of what it's capable of; but there's several different ways to deal with each party. So long as you're slightly more careful about team synergy and what each member brings to the table/focuses on you can probably do fine.

Technicaly they were feasible in every EO game, it just meant working smarter (EXP is divided among party members, so you won't need too much extra grinding since you'll get more EXP anyway)

[Snowdome]

I believe that's perfectly feasible, but the risk increases dramatically when you face a monster group/FOE with heavy single-target ability/instant kill/petrify.
Actually basically any status aliment will become relatively more deadly than normal damaging abilities with a smaller party imo so maybe that's where you should play more carefully.

[Doktor_Q]

In EOIII, you could one-man most of the game with an Yggdroid subclassed into something else, if you were patient.

In EOIV, it's looking like Fortress/Bushi might be the go-to, for incredible durability and a good dose of self-recovery. Of course, some enemies will just generally take you out, but still.

If you want something like a 2-4 man party, that's totally doable too- you just have to consider what roles you need, and specialize a bit more.