On multiple subquestions in the same post
One of the major warning signs for a question to be "too broad", or to use the new name "needs more focus", is when it is asking more than one question in the same post. It even says that in the close reason itself:
This question currently includes multiple questions in one. It should focus on one problem only.
If someone asks multiple unrelated questions in the same post, then that should be closed, and maybe edited or broken up into more than one question post. To stretch the point to an obvious case, I think we can all agree that "why didn't they use the Eagles to fly the Ring to Mordor? and what exactly is Tom Bombadil?" should be closed and split into two questions.
On the other hand, not every post with more than one question-mark in it should be closed! Sometimes there are multiple related sub-questions which are all part of the same main query. That should be fine, and that seems to be what you're referring to by "guiding questions" here. I'm not going to try to wordsmith a policy to define when multiple questions should be considered "related" and when not, as such things might need to be decided on a case-by-case basis, but certainly there are cases of both types. Your question counts as a case where the different questions within the post are related enough that it shouldn't be closed, and indeed has been reopened before this meta post.
How to convince people that multiple questions in one post are indeed related?
(Not for your question, which has already been reopened, but as a general principle.) If people are voting to close a multi-question question as "too broad" / "needs more focus" even though the questions are related, consider editing the question to make that more clear. Try to put yourself into the minds of the close-voters, and assume good intent. OK, they think it's too broad because there are three different questions in it; write something to address their concerns and convince them that those questions are closely related enough to fit in one post.
That "assume good intent" part is important, by the way. You're much more likely to convince people by trying to see their point of view than by attacking them. Using terms like "close vote mafia" doesn't help your case and won't endear people to you - even if your main point is correct!
What about those multi-image ID questions?
Certain topics and types of questions have their own particular history on this site. People have been posting the occasional multi-image ID question since years back, and it's often more about fun cooperation and community building than a question that the OP really needs answered. They've been discussed on meta before, and some people do think they should be closed as too broad, but they're generally (if grudgingly) accepted since having them around has never caused any trouble. If you want to make a case for closing them, open a new meta about that.
People abusing close votes
In some ways this site is indeed quite close-happy, and some users more than others. We do have a number of questions getting wrongly closed, although a good proportion of them do get reopened afterwards. But there are different degrees of what might be considered "abuse" from close voters, with correspondingly different levels of mod action possible.
- If a question very clearly shouldn't have been closed, I'm willing to modhammer it open (and take the flak on meta from the close-voters if necessary). But some questions are pretty borderline and I can see both points of view on whether they should be closed or not.
- If there's a consistent pattern of clearly inappropriate close (or reopen) votes from a particular user, we can send a moderator message and remind the user about whatever scope policy they're ignoring. I've done that once or twice in the past. But, again, it's harder to justify taking action in more vague situations, where people just have more or less strict interpretations of scope policy rather than acting way out of line.
Note that it (usually) takes five users to close a question. If there's just one or two overly strict close voters, it's not enough to get lots of stuff closed. You mentioned a "bandwagon effect", which is sometimes true but IMO not (as you suggested) a natural consequence of the Close Votes review queue's existence. That queue has two buttons, and sometimes a question escapes it quickly with unanimous Leave Open votes. If a question gets closed by five people, and doesn't get reopened afterwards, that might be more of an indication of some actual consensus rather than just a few people misinterpreting policy.
I'm aware that that's not always the case, and sometimes even valid reopen votes fail to gain traction (e.g. if the same people who closed a question just quickly vote to Leave Closed in the Reopen Votes review queue and nobody else even sees it). I know that this is a problem, but I'm not sure what to do about it, even as a moderator. Part of the problem is more from the nature of the system than any particular bad actors.
For what it's worth, most of the controversial closures on SFF are duplicate closures. These are the exception to the rule that it needs five users or a mod to close something, since some high-rep users have gold tag badges and therefore dupehammers. Partly due to this, and also a hotly disputed meta policy, a lot of dupe closures are contested and controversial. That's a discussion I'm not getting into here, though :-)
One last point: you've put a lot of emphasis in this meta discussion on a couple of high-rep users, but it's worth noting that they were not the ones who put your question up for closure. It originally entered the review queue due to a close flag from a low-rep user (someone without even the 3k rep required to VTC themselves), and was removed from the queue after three Leave Open votes (as well as three Close votes), but then went on to receive two more close votes not from the queue.