abandoned or half destroyed structures not in use.

I could have a serious problem with that to be honest. Because you'll never know what you'll find. It wouldn't the first time where such a ruin is actually used to cover up something else, like a railway. Something you'll dig up when you remove it and then you'll have a hard time concealing it again.

Some players actually use ruins because those wouldn't attract any griefer attention in the first place

This yet again comes down to using some judgement and really knowing the area. wylliemo or Shell could be correct. It really depends on context.
For example, out at Wild North, there used to be a little wooden shelter and glass pane rainbow off the public utility road. I didn't see who built them, but I saw them go up at the same time. They were both griefed months and months if not a year ago. There are like 4 wooden stairs and a plank left of the shelter. Half the rainbow is still there. I don't really recall what the shelter looked like, and it was griefed until it was gone basically. I'll probably whack down the 4 pieces of wood sometime since they are hanging in the air just looking like trash and giving shade for critters to spawn off what needs to be a safe public road. The rainbow is 50% or more there and I'll probably try to repair it. If I ever get time and get around to all this.
We really need to be thoughtful and careful if we're going to pursue this. A big part of that is knowing the kinds of details I just spouted off. If I didn't know those details, I'd check with a mod before touching it.

In the mean time I won an auction for 3DC's of dirt. No, I was actually thinking when I placed my bid on that auction: this dirt will be dedicated (and made available) to/for those who are going to help restore things. You know: fill up holes and such.

This weekend I have a few other things on my mind, but next week I want to try and actually start to get some kind of group together. So a group of players, preferably from all different SMP's with the sole intent of helping to restore the frontier.

My idea is to try by starting to set up a conversation with all of them. So that we can eventually help each other out. For example: "I found this structure at SMP3, coords: X, Z. What do you guys think we should do?". Or: "We're planning on restoring a grass field onSMP6, can anyone help?".

And of course it would also be used to discuss the upcoming policy draft. My idea is to start that in private so that we can chat about these without risking to get a thread spiral out of control (because we will be discussing the rules and there will be opinions shared).

So next week I'll fire up a new thread which will specifically ask players if they're interested to help out.

Idk I wander the wild quite a bit and I enjoy exploring old structures and outposts, even if they are partially damaged. It gives a bit of mystery to the area. What happened here and who used to live here?

Or another option is that you could repair the structure.

These are all wonderful ideas and I would love to help out with any of them, but here is what I got to say. We can fix stuff all we want. Remove all the lava and water that has been poured onto once amazing monuments of EMC craftsmanship and fill all the holes that have been punched in them. But until the whole thing with the land protection goes up, Greifers will simply return and destroy all the hard work that was done to repair it, unless it's like really far out or something. Really I've never seen any Greifers on EMC, yet structures always get destroyed, I find that I'm not surprised as much as I used to be when I fall into a trap meant to kill a Greifer anymore.

Mattias, we're only talking about the areas in the immediate vicinity of the wild spawns. There's nothing like joining a server, going to the wild for the first time, walking 30 blocks and seeing... well, not nice stuff in some cases. It's a bummer. We're only thinking of doing this for a certain # blocks from spawns in the Frontier.
Shadow_Dcord, I know that struggle, especially with Public Wild Utilities. Yeah, I know man. It's a battle worth fighting for though

In the days before the wastelands, the area around the spawn was the place to do all the mining for resources. Since they have implemented the wastelands, the admin said those areas would never again be reset, so people have begun to build closer to the spawn areas. To reset those areas would also destroy a lot of active player structures.

I agree with Khixan. I have a friend and no matter how I talked about the positives of this server when he saw that area he decided not to play on Empires. He was a bit too picky but I'm guessing he's not the only one.

Nice big site like this we get our share of noobs and transient players that come on for a short time never to be heard from again. The scraps they leave behind are the things I am mainly talking about. But you're right, it can be hard to determine which is which. I hide things too, but employ more subtle markings or the coordinate system.

I also should make it clear that if there is a locked chest or sign that says who owns the place, a quick /p (player) would let all know if that person was still active - any site belonging to any active players should be taboo for any cleanup activities! If it does look like a forgotten structure, a quick message asking them would be the way to go.

Often when I am out I will wall in a little cave and put a door on to hide in, and I always place a sign by any chests I leave behind stating that stuff is free to take for anyone who finds it (usually because I am very lost and getting rid of junk)