I think I have mentioned this before, but I am willing to be a partial moderator like what notaz described, basically just dealing with spam and maybe merging or moving threads if it is really needed. I would still want real mods to deal with actual user stuff. Basically, I just don't want the mods to hate their job, so I will deal with some of the stuff when I swing by, and they can deal with us when we are being stupid or getting too emotional, or whatever else they deal with.
As for the proposed image based request to enter the words from the logo, include it in the languages of the countries where most legitimate accounts come from. If those need to be translated I think it isn't that difficult to type the thing that needs to be translated into whatever they prefer to use for translation (I do this with old books and manuscripts I look at pictures of). It isn't perfect, but it might have more benefits than drawbacks, so it might be worth seriously considering. This method would make it easier for spammers that know the language to get through easily, while real users that don't have a more difficult time registering. Alternatively, the "find the registration password on the boards" thing should still work (and it can be changed quarterly it as needed), and including that means that the request for it can be kept as actual text, even autotranslated based on the language of the IP address. The only other decent options I see are those previously suggested restrictions on new users, and that only deals with posts, not those who abuse profiles.
Is there any sort of pattern with the email addresses used by the spammers? I know that I can't use mailinator for registering at some sites, so maybe something like that could be done here.
[doublepost=1488696625,1488696514][/doublepost]Mods, maybe this thread should be moved to the site feedback section.