Well, when I played with broken banter for dozens of hours in DAI the experience got pretty close to a solo play already. My companions followed me in silence, and the moments where they would comment during a conversations were pretty rare as it was. Even when the banter was working, most of it isn't interactive, so they were mostly talking among themselves - but not to me - while we were adventuring.
Truth be told, I've come to think that even a pure action game like Vermintide does party banter occasionally better than DAI did it. While it certainly has less overall lines - it's just a co-op MP game after all - it really brings its characters to life because it is so context sensitive, always fitting the situation on hand. DAI banter lives from conversations outside of combat, Vermintide just lets the characters talk as you would expect companions in combat would do, by making them comment on what is happening around them.
Bardin (dwarf ranger): "Not to brag, but that was the cleanest kill I ever made."
Sienna (bright wizard): "And so modestly expressed, too."
SIenna (after another player achieves a kill streak as Sergeant Kruber): "See, Kruber? You can be fun when you want to!"
Bardin (reviving the elven waywatcher): "Did a gust of wind catch ye, elf?"
(when the skaven spring a surprise attack)
Sienna: "It's an ambush! YES!!"
Victor (witch hunter): "If we catch one alive I will be the one to interrogate it. This is not up for discussion!"
This context related banter makes you truly feel that you're fighting as a group (even if you choose to play with bots). I'd love for Bioware to implement something similar, maybe in addition to the banter conversations that are largely unaffected by the region you are in or the quest you are on.