It really bothers me

Smarter than a lot of people anywhere. :P

Good point.

Now to work on those traits.

I actually kinda like when people don't pronounce the Ts. Only in some words, though. In most words it just sounds ridiculous, but in some it sounds nice to me, like better or matter.

...dear god those are some of the worst for me...

It really depends on the voice of the speaker, I think. And also the intensity of hearing these words. Since I'm not a native speaker, I hear these words and this accent very rarely, which means I kind of liked it when I heard Rose from Doctor Who say it, but hearing it on a daily basis would probably drive me insane, I admit.