They have been using old critter graphics since 1600 I think. Chill wind wolf at 1608 was the first I noticed - then I had a look and saw all the other creatures then were reused, and I think that has continued. 1600+ was I think the beginning of the 25 level releases, after the epic that was Crestoun etc and the arc that led to the terror titan. It was fun seeing old faces with new bodies, and no-one seems to have cared and not many noticed - many of the critter names remain the same, just updated to new realm solaufein etc. So that was a suggestion that was acted on, and it is a little sad that it has not helped content release speeds - I suppose this means we can no longer blame it on artists dragging their feet! (Also - losing the common items was another reason content releases were supposed to speed up as that was more artwork that was a waste of time as no-one ever used common drops at those levels as a result of the co-ordintaed/SH/KE bus bonuses. So no need for artists to create more pics of boots and shields etc. no-one was going to use. Reusing item artwork is problematic as in the past accidental duplicate images of items caused unfortunate confusion and mistaken buys in the Auction house.)
Maps - yes I think if you reused old maps and just move the entry and exit stairs around few people would notice. The artwork re-use didn't cause storms of protest.
I did put in an idea a while ago - complete with suggestion for reuse of critter images, in reusing entire zones of the game in an alternate (nay Doctor Who??) type reality. Though my specific idea was a shadow realm of Xinderoth, an inverse run through, from top to bottom as an epic dungeon bash to find the huge ruins of a lost underground city at its base ruled by a lieutenant of the Shadowlord. That would reuse maps and critters, but would require new quest lines - which I'd happily dream up if it was going to happen! But yeah - having shadow realms created to block our hero's path and test him could be used as an occasional 'greatest hits' theme to reuse old funky game areas that are nicely thematicaly linked - morukan, the lenzwer forest etc. etc.
And we have the discarded realms that used to be at the start of content and have been edited out and so are all lost and without a home... they could be reused without guilt, though I liked them as a home to a storybook forest/quango style intermittantly released realm event, with its own storyline and bosses - as I think I said in some other long winded post.
Obviously there is only so long you can go cannibalising parts of the old game to go forward.... eventually all the critter pics would have been used twice, and some are unique and should not be reused. Maps - well some are very obvious as belonging to one area, but most are fairly generic - I hope that map creation is not that hard and is not the reason for delay of content - depends what the level editor software is like I suppose.
Once upon a time we got 10 levels every 2-3 weeks, and it was like that for a long time as I struggled to catch EOC. That started to slow down, and then we got 25 level chunks, and initially that seemed cool as one 25 level chunk every month still put us ahead of 2 10 level chunks per month... but the 1 release every month has rapidly faltered, and so we are left with nothing for weeks/months at a time, which is sad. We have not had any detailed new areas since Crestoun etc, and as that was under 200 levels ago that seems fair - fgiven the Xindy- Karthak - Crestoun spacing, and such content is a lot of work, I would probably only hope for turbo content in the lead up to 2000. Though I'd take stuff before then gladly!! Therefore detailed level ares are not the reason for slowdown in content release. Focus on globals/ legendary release events/composing may be to blame - I don't know, I don't work there.
The point I wandered away from is that content shouldn't take that long if you are cannibalising pictures, and eve less if you cannibalise maps. (And we still have hundreds of levels of stuff to use before we get to using things a third time around) But if it is a one man team (BG, or BG plus small number of folk) attempting to juggle content plus legendary releases, plus globals, plus seasonal events, which cannot be delayed - the hallowe'en event must go out on time, hitch free, very rapidly followed by the bonfire business, and then Christmas is breathing down the FS content team's neck - you can see how basic content gets shoved to the bottom of the pile pretty quickly. Problem is, lack of content does cause dissatisfaction and loss of interest in those players who have been engaged enough in the game to want to get through all available levels. I am not saying they are more important than any other segment - at all. But they are engaged, and have put many many hours/years in to get where they are, therefore it seems sensible to keep them playing. Content just has to keep rolling out to keep people engaged and interested - yes there are other things to do at EOC- but it is not a stretch to think that someone who has gained 1750 levels, just likes gaining levels and would like to gain more, it is a primary and simple joy in playing the game. Cynics - feel free to laugh. New content is a core function of the developers, its failure to appear indicates, in my opinion, either overwork or lack of focus. I know BG has mentioned he has content creation on his desk - but many other things are too - i.e. too much for him or his team. Would he accept help from the players? Could he without appearing to play favourites? (the competition idea is cool - but is it legal? If they are not allowed to employ players, could a competition to create content questlines be seen as a form of employment by proxy, as the company will obtain a product from which they derive profit as a result of said competition?)
Is the delay because new content causes problems in that people will start asking where are the 1800 buffs? Then sod them, make the next lot of buffs at 2000 - we don't need more anytime soon. That handily delays that major coding headache - and new buffs must be a PITA to integrate into the existing web of buff interactions. We have seen enough glitches here and there to know this to be so - so we take the pressure off and not insist on new buffs.
Anyway, there are my thoughts. I still really love the shadow Xinderoth idea - with a new Shadow Xinderoth SE who hides in the huge base map and must be found three times before you can even hit him as he keeps teleporting away from you! It should be hard to find and hit him - at EOC/ the silly high level at which this realm would appear, we have the time and stam to do so.... right??
TL;DR