Simplex is looking great so far. Some thoughts after the link to my 4 demos. I had a long day between yard work and Speedmapping 182! So my playthru is terrible but I have some notes embedded in the demos. I'd suggest using Mark V to view them because it has FF and Rewind! You'll need them with my demos:
https://www.dropbox.com/s/imdm7mtrfjqjaxj/simplex_b1_dumptruck.zip?dl=0
okay some thoughts:
*Yeah you def need more enemies but not a LOT more IMO. I like quiet moments but currently there are too many. Also, you need quality encounters as opposed to the quantity. So for example: You have no fiends in your maps but a lot of loooooong hallways. Fiends are designed for long hallways. Throw a few in your next beta in strategic areas. They do get stuck on stairs and in small corridors but you have a lot of areas where fiends can introduce tension and OMG moments.
* You need some Vore / Shalraths in this. They are great with areas where you have a lot of cover. And your map has a lot of columns - this would be perfect for Vores. They aren't too hard to beat if you know what you are doing so don't be afraid to use them where the player can take cover to avoid. Just make sure the player has enough ammo to deal with them.
*with more monsters you need more ammo and armor. Use your puzzles as places to reward the player. There's one area where I hit the wall with the ax. (Large area with jumping puzzles and water underneath.) That would be a great alcove for armor to reward the player for making the jumps.
I LOVE the jumping puzzles overall. I noted a texture issue in the first demo. When you hit a button the texture should go from animated to non-animated. I got fooled for a second thinking I needed to hit the button again (duh me). I know you are "gaming" the system by looking at the map because the whole thing is a func door. However, you COULD try having the button on the func door have the texture of the "off" position of the switch. (+abutton) Before the player triggers the func_door you could overlap that brush by one unit with a brush with the animated texture on it. You make that a func_wall that will be "killed" using a trigger relay and killtarget.
I copy and pasted an example from your map of this into a test map of mine:
https://www.dropbox.com/s/84mc8pimfm57swd/simplex_example.map?dl=0
It's a small thing but small things add up and it's not too hard to do. Quake has a visual language that we have to stick to and this is a good example of something subtle that can confuse a player.
* Think of enemy combos for this map. When to use ranged enemies like the Zombie and Wizards as opposed to Knights who are melee only. try different combos in different situations. Ogres below the player are pretty useless as I noted in the demo. I use Hellknights for those situations.
*The funiculars. I picked off a bunch of enemies from above before activation as you'll see. Trying setting them to the "ambush" spawnflag. They will stay asleep until they see the player or are fired upon. You don't have to fix this in this map but here's some food for thought: After the player activates the funicular maybe delay it for a second and teleport in those monsters so savvy players can't kill them before they are a threat.
Those are plenty of notes. This is going to be a cool map. You have some really unique game play ideas as with your first map!