I don't mind some of the liberties they're taking with the comic. It's like they're fleshing it out and making it more real. They have to take their time with it a bit more since the comic has to cram in a lot of information every month. Each story arc is only 6 issues.
They're probably trying to emulate Kirkman's writing style where things will be pretty calm for a while and then BAM, someone important dies, changing the way everyone interacts with one another.
I'm sure the acting will get better over time. Unless it's like Heroes, where it just got increasingly worse. Actually, Milo Ventimiglia got better, and Hayden Panettiere got much much worse, which brought down my entire opinion of the show.
If you haven't read the comic, don't open this spoiler: