I personally think the Terrarium should be removed cause since the introduction of Kit-pvp it is now useless. Once remove you can replace it with the dungeon. Keep it just as complicated if not slightly more as that is the whole point to go in to danger and get a reward!
t would have been easier to say "replace the arena with the dungeon", which would actually be really cool because if it includes a giant "
~ @leodavinci9000
I pretty much agree however with slight modifications, I think that the terririum "areana" part should be removed and you can just make the actual whole dungen the arena floor. I had something in mind like this:
Brown parts = medium-large tunnels enough to pvp-pve (with light/medium mobs scattered throughout)
Orange-brown parts = main pvp area where you can jump down into (I imagine some kind of old castle ruins but with enough space around them to pvp properly and such).
Blue things = ladders to get out only.
Yellow things = chests with prizes (guarded by crazy mobs of course, and the further to the back of the dungeon the more mobs that are spawned and better the rewards).
Also I think the dungeon can be more like in my picture not too much up/down (i mean it can slightly) but the base floor level should only have a +/- 5 block difference from the spawn.
(imagine you are looking down from above, this is like a photo from the above)

I have to disagree with you on terrarium. Terrarium should not be removed, imo because it is the only self rewarding true pvp.
~ @smk
The terrarium by itself I think is a waste of space I do like the idea of combining the dungeon and the arena for pvp-pve please see quote above here for more thoughts. (this is not like it was before basically the pvp-only part will be much less emphasized (meaning you actually have to "hunt" for your kills not just slaughtering them). You will still be able to pvp only if you stay in the larger spawn area and you can also run around the dungeon to look for other players to kill as well but you will have to evade mobs in the tunnels.
I don't understand what the picture is for, it's easier to improvise dungeon rather than copy something because they need to add traps and obstacles and such
~ @Acceleradiance
The map is just the IDEA of how it should look you don't copy it duh, cause then everyone would have a map of it!don't think there should be too many exits otherwise it's extremely hard for people who came to pvp to find and kill other players.
~ @Acceleradiance
Yeah, at first though it was just because people said it was so hard to get out, and like the old dungeon their was only 1 way in so camping that would be to easy.... perhaps using the map just remove the exits in the middle and only have 2 at the beginning and 1 at the very back (guarded by mobs and stuff) where it very hard to get out (but still possible).
Revised less exits in blue now (only 3 instead of 7):

If they were combined they could be called the Dungeonarium? or Terrariungeon?