Having finished reading it, I do agree with the bottle episode format being at times useful although I think too many bottle episodes in a row does get boring and some of them just fail to accomplish anything in any capacity other than filling out the season.
These could have been done interspersed with more progressive episodes that show the characters in a group or at least larger than two-three person groups. And though we now have three new characters "the Mullet, the Mustache, and the Midriff" to work with they haven't been seen in a few weeks.
We got only a taste of what their personalities and motivations are before moving off to another bottle. It would have worked if they were kept for later in the "six pack" of bottles we've got here, so that instead of meeting them then abandoning them for several episodes, we meet them near the end and continue to see who they are.
There are points to be made about the larger story being too simplistic at times "Whats the point of living, are we a democracy or a monarchy, etc etc." where it just seems like they are throwing out ideas with no idea how they want to address them. They give us ham-fisted, generic answers and hazy, lazy and iffy solutions that as quickly as they make them are either lost or discarded (their democracy was a joke, Rick's leadership skills are barely passable, no one seems to stick to a concrete plan).
The upcoming episodes getting past these bottles will prove how well the story is going forward. I do think they were necessary but not necessarily in the way they were written and the order we got them in.
After everyone(?) presumably makes it to Terminus they'll have to address how the group will fit into this larger community, how they will address the ongoing undead and living threats to their survival. Who will stay, who will go and who will become a part of their little group?
Season five, which should be helped by not having to carry the remnants of the previous four seasons, will give us an idea of where Gimple really wants to go. I see everything else to this point as basically playing catch up and damage management from the last several trainwrecks of new showrunners and changes in the story.