I'm not talking about MORE dialog (the resources dedicated to that must already be staggering), I mean a better system for the game to determine when/if a line of dialog is appropriate.
Some things should no longer be said once certain conditions are met, and vice versa. Some examples:
Connie Abernathy remarks she doesn't trust strangers, so "you'd best be movin' on". Does it really make sense for her to keep saying this after you've done the Abernathy quest, gained her trust, and technically own her land?
A caravan guard growls "Make a move and I'll END you, wastelander." This line should be disabled when the caravan is inside one of your settlements. Would he speak to Mayor Hancock that way when in Goodneighbor? Not if he likes keeping his blood INSIDE his body he wouldn't.
And a memo to all settlers: "YES, I know Graygarden is run by robots. I own it." Settlers should stop telling you about places you've visited (especially if you've built a damn village there).
I love Bethesda adventure games, full stop. That being said, the idiotic NPC dialog has always been one area where they faceplant. I murdered several unimportant NPCs in Skyrim just so I wouldn't hear their lines anymore (Q: Do you get to the cloud district very often? A: *removes Nazeem's head with daedric greatsword, hands 4000 gold to nearest guard* -Worth every penny).
Seriously, Beth, there's no reason for this, given the attention to detail other parts of these games recieve.
/end rant