First hub, is a much loved medieval hub
First level starts in front of a keep, but more inspired of Amulets & Armor design rather than Hexen
Wide courtyards,
statues everywhere
trees everywhere
Not much to say here, it's standard, but it's good. Will the keep have some sort of neat means of breaking in? Maybe not catapulting yourself over like in the original, but perhaps setting up a battering ram and then obliterating the door with it (if the engine can do something like that).
Next hub, is some sort of desolate wasteland?
Lava exists here much, maybe some dark stone buildings here and there
architecture style undecided?
stalagmite ville
Sort of a mix between Hexen wasteland and Heretic early E2? Sounds cool. Maybe replace those Mesoamerican heads with some other sort of stone head that would look cool here, skinned to look similar to the primary rock textures that get used and all. Just have some standing lonely on a crag or stuff like that.
Romeric hub is really a large tall tower
Will it be a Romeric-themed tower, then? With those style columns for supports and all?
atlantean world, with water domes and such (like Heretic)
How do you plan to do the domes without a skybox, will they be brushwork? Maybe some subtle (not too overt) Lovecraftian influence here, like those elder1_* walls I submitted.
this hub is the snowy hub
there is an ice castle here
there's also some
Maybe some pine forest sort of stuff for the outdoors? A big frozen cavern in the lowermost part of the hub? Wolf-themed and/or Norse-influenced decor?
the final hub is a really evil big epic massive fortress of some sort
epic church organny music building up toward the last level
Lots of evil/hellish stuff here I hope.
where you face the big red guy whatever he might be
Hopefully Not Red, for starters, that looked really cheesy on both him and the Heretic gargoyles...
Overall it sounds pretty good, the main thing that comes to mind that would be cool that I don't see is someplace with lots of tombs & stuff, but maybe there could be a tomb level mixed into one of those other hubs (The medieval one? The ice one? The evil fortress?)