Making Dungeon Rooms More Tactically Interesting

A few days ago I posted a combat maneuver system for OSR games.  I like combat in which people are getting shoved around, random objects are getting thrown at people, and the like.

The thing is, you need something to shove enemies into.  "A wall" isn't a very satisfying answer.  Also, fighting in featureless rectangular dungeon rooms gets boring fast.  

Solution: for every new room your players enter, roll on the following table.  If it's a really big room, roll twice.  If you're playing typical fantasy D&D, roll a d12, if you're playing science fantasy that has guns and computers and stuff, roll a d20.   

1.  One of the walls is dangerous– covered in spikes or something similar.

2.  There's a bonfire in the room.

3.  This room is split-level– half of it is about 3-5 feet higher than the other half, enough to give a significant advantage to people on the upper level fighting people on the lower level.  There's a stairway (or two) in the room.  

4.  A pool of water, acid, lava, poison, toxic sludge, molten iron, mercury, or whatever is most appropriate to the dungeon.    

5. There's a big reflective object– either a mirror on one of the walls or a shiny orb in the middle of the room.  It will blind anyone who is a) looking at it, and b) carrying a light source that shines at it.  

6. One or more solid tables that could be jumped on, or flipped over to provide cover.

7.  Several statues, free-standing pillars or similar objects that could be hidden behind (just barely, partial cover only) or tipped over by a really strong person.  

8.  One or two long bookshelves or similarly-shaped objects that could provide full cover, or be tipped over onto people.

9.  Ropes or chains hanging from the ceiling that could be swung from.

10.  A circle of protection from magic is drawn on the floor, covering one or more dungeon tiles. Nobody can cast spells in or across it until it is physically erased.

11-13.  Nothing, this room is pretty boring.  

14. There's a big Tesla coil emitting sparks and lightning, or maybe just 

15.  A big buzzsaw or some grinding gears or something that you wouldn't want to be thrown into.  

16.  There's a security camera here, 50% chance it's wireless enabled.

17.  Electronic door(s), 50% chance wirelessly enabled.

18.  There's a loaded gun or hand grenade near the middle of the room.  If an encounter takes place upon entering the room, the weapon is exactly halfway between the two parties.

19.  Something in this room is jamming all electronic signals.  Or maybe the whole room is just encased in a Faraday cage.    

20.  Remember the death star trash compactor?  Yeah, it's like that.  

Note that these are different from traps in that they should usually be immediately visible.  Generally the idea is that they weren't put there specifically to help or hinder invaders; they're there for some other reason but clever players can make use of them during a fight.