The Culture explores 40K II: Now With 100% more Fanfiction

[jseah]

Some Culture people would notice this in their history, and put into question the assumption that they would stop just because they took some major losses.

That is fair enough, but it also doesn't square with the stated difficulty of replacing ships and troops. The Ultramarines were noted down as not being able to be brought back to full strength for over a century. And there aren't THAT many space marines in a chapter anyway.
A Lunar was cited as taking years to build. One bloody cruiser.

If they can change the situation so that the Imperium ISN'T beset on all sides by forces that want nothing more than it's utter destruction (with the main difference being how soon they want it), then you'll have a much better point to start working from.

Agreed with Tiki. As a salient example, most of the fascist style darkness is because of fear of Chaos, for the most part.

So let's see,
The tyranids are soon to be a non-problem. They might nom a few planets, but the Culture just wipes them out wherever they run across a fleet.
The orks are going to remain a pest, but also a non-problem.
The Eldar and the Necrons, the Culture does not control. They treat them as similar to other Involved civilizations. If they attack the IoM or each other, the Culture will not interfere.
The Tau about to become a major problem. At least after a few years.

The Culture want the IoM to be less oppressive and less xenophobic, as well as less AI-phobia, and less theocractic and more technocratic.
Which is about as likely as... as well, the basin of water in my kitchen suddenly freezing over. At least, as long as the Warp exists.
And they want to do this by:
1) not making Chaos a more major problem than it already is
2) preferably not involving a bloody revolution/collapse

That is the thing they are going to try, and my feeling is that it will end badly. You can't give them any tech without first solving the Chaos problem, and implementing the solution for the IoM. And 'solving' Chaos would require them to shut off the warp.
Which would result in a bloody collapse. The solution to that being giving the IoM tech, which you can't do until you 'solve' Chaos or you will make 'solving' Chaos a whole lot harder than it already is (which is nearly impossible)

It's an impossible situation. And if the Culture had to choose between 'solving' Chaos and the bloody collapse, they'll choose the collapse.

Why even bother? If you're driving along in a car and a dog starts barking aggressively at you, you wouldn't get out and murder the dog. It's just a dumb animal and it can't possibly hurt you.

They might be able to. The IoM uses Warp technology and psykers, which is still an unknown.

In the analogy, it's not a dog that is barking at you, it's a magic mist that might bite your arm off or not even scratch your hairs.

EDIT: the thing here is that they either break up the fleets or just avoid them altogether.
And they can't really do the second since they can't track fleets in Warp.