Of all the recurring excuses about why a party of four would be great the one that I detest the most is quite possibly "Less slots encourage diversity between playthroughs". No, they fucking don't. When you have basically no room for any type of role redundancy or for less than optimal classes for your need, more often than not you'll find yourself reserving some crucial slots for the same key companions (or a custom-made equivalent) and constantly excluding the same sub-optimal ones.
And NO, having room only for two characters in my party wouldn't make me wish to play the game six time to experience all the twelve classes, it just makes me look at classes I don't particularly love and say "Well, tough luck, sucker".
This is SO true. You know why Wyll is hardly ever in my party? This. This right here. To me, he's not worth it. Why? He's squishy, doesn't deal much damage, and he can't cast a lot of spells.
You know who else tends to get kicked? Shadowheart. One of THE main people because she has the relic. Why? If I'm a druid. I have healing. Don't need her. Even if I don't have another healer, potions can be thrown and sometimes heal better. Anyone can resurrect.
So, if restricted, bye Shadowheart. This is a shame, because I like her, for the most part. Wyll too, really.
This is why especially I hate party of 4 in Multiplayer. Can't bring ANYONE THEN.