The classic thing is that you summon a pixie to Polymorph the party into Dinosaurs, and then it doesn't matter about concentration because you are considerably stronger than most things. Its more of a meme thing than something practical. And I am on your side with the fact that familiars should not be conflicting with concentration conjuration spells, similarly, features giving companions like a Necromancer's undead should not conflict either. Also we are likely not going to have the Dinosaur TF thing cause I don't think Faerun has dinosaurs, or atleast doesn't have them anywhere close to Baldurs gate.
