I suggest removing the giveaways with no keys left from the giveaways page

Strongly agree. Plus, make it so that the giveaways sort themselves out by date, with the newest giveaways on the top and the later ones when you scroll down (if the giveaways are not sorted out like that already). It will be interesting if there is also some sort of level sort where giveaways above your level (those that you cannot access) is automatically not shown unless you click in some sort of option settings to show all giveaways including those you currently cannot access. 

Agree and also try not to spam it on other sites because bots take the keys. 

Great Idea! 

Or just make the pictures gray.

So, its the mark that the promotion was announced and its clear that its ended.

That can be can be automated.

I agree, just remove the ones without any keys left