I have top disagree on point 2. One a question is deleted by a moderator you can only bring it up in meta. You can't vote to undelete anymore (maybe other moderators can?). For anyone who has powers gained through the points, mod's deletion is final.
And that's sometimes very annoying since those deletions require only one person. No voting, no double checking. Delete-happy mods can definitely abuse it.
Whereas a "delete-happy" mod can abuse their power, another reasonable mod can just as easily reverse it.
As far as mods that tend to be trigger happy, they can be filtered out since mods are elected by the user base. Technically, you can choose who you want spending their waking hours going over questions and filtering out what shouldn't be there.
That's why I said you can vote counter to most moderator decisions. That's the one thing that only another moderator (or employees of Stack Exchange, who oversee moderators) can reverse. And no, "delete happy" mods cannot abuse it. There is oversight by other moderators and the Community Team at SE.
I've seen enough questions killed that way that yes - I consider it easy to abuse. It happens all the time but if it happens to someone else's question it's not worth my time/energy to raise the issue on meta. The lack of balance here is what makes it really annoying to fight.
If there were no mods with decisive power and it was completely up to be controlled by the common population (including people who sign up with multiple accounts), how does that help? How does multiplying the amount of people with power make it less annoying to fight an issue?
Reputation thresholds minimize this problem to begin with. Any remaining problem could be largely eradicated by focusing enforcement efforts on those people instead of exercising hypocritical control over what content the community is permitted to deem worthy.
It would be interesting to see exactly what number of the community actually wants discussion posts and how many don't. Currently it is the community that votes to put a post "On Hold" before a mod comes around and verifies that it is a legit post that should be "closed." It is brought to their attention by the community who do not want it there. (And not just high rep members of the community.)
It's not abuse if moderators are deleting questions that don't belong on the site to begin with. If you don't care strongly enough to raise the issue, perhaps the question was rightfully deleted after all.
I'd prefer they just closed them. There's a difference. Also if I disagree with community moderation I can say so or vote for the reverse action. Not so with diamond mods.
It's also a community site, not my job. Even if I care a lot, dealing with meta is not worth it in most cases. I look through the close votes whenever I have spare time, and would appreciate if other decisions were also taken in the open rather than by one person who may be especially grumpy that day.
I'm not arguing about contents of the questions - some are stupid and deserve closing/deletion. Just want to make sure those decisions are always reasonable, accepted and possible to revert.
And that's sometimes very annoying since those deletions require only one person. No voting, no double checking. Delete-happy mods can definitely abuse it.