I had this idea for creating some new destructible types. I was thinking over gameplay and how destructible rocks effect gameplay and such. Ever since the new idea blizz had for hots destructible rocks, I thought over it and came up with other kinds of destructibles.
Destructible Chest: May be destroyed to reveal a patch of minerals that give 100 minerals if walked over. Players can use this to get an early or late advantage depending on where it is.
Destructible Pillar: Can be broken to force it to fall and create pathways over empty space that can't be walked on. Players can use this to create new pathways into other areas. May also be placed by mappers to force players to destroy them to get to a player without air.
Destructible Cliff: May be destroyed to force rocks to fall downwards. Any units under the collapse will be elliminated. Mappers can use this to help harrassment by placing it in bases or place them at chokes to help defending.
Destructible Ground: Normally may actually be walked over, but if destroyed, it breaks the rocks and there is now a hole and that ground may never be walked over for the rest of the game. Players can use this to force their opponents to either go air or around that pathway. For example, there is a main path towards the enemy and a longer path. The shorter path has destructible ground all along the middle. If it's all broken, the pathway is lost and players must now go the long way.
No idea what this thread is going to do or how others will react. You can ask questions, add some more ideas, try to make these, or just comment. I had this idea and didn't want it to go to waste. I may also come up with more ideas. I had maybe a few more ideas already, but don't remember them, so I'll be back. :)
Destructible Bush: 2x2 space bush with 10 life. It blocks movement and sight. It's a very interesting destructible, because when destroyed it auto respawns after about a minute. This makes gameplay very interesting and different. Mappers can use this at entrances to expos to trick players into not knowing somebody has taken it. This may also frustrate the player expanding because he has to break the bush every time he wants to reach his base.
Destructible Bridge: Not exactly destructible, but the bridge has 2 sides. Each side has a power generator, pylon generator, or a swarm generator depending on race. (Meaning 3 different versions of the bridge are available) Generators share life. If the bridge generators are destroyed and the bridge is active, the unit respawns instantly, morphs to deactivated version, and applies a behavior that makes it invulnerable for 10 seconds. And vice versa. If units are on the bridge while it's deactivating, all of those units fall down until they hit pathing and then die instantly.
Interesting ideas, though some of your ideas aren't at all viable. A destructable pillar for instance is exactly the same as making a pre-build pathway and putting regular destructable rocks on it. Destructable cliff seems a bit pointless. They'd be too easy to maneuver away from if they have too much health, and if the defending faction decided to take the cliff low so that one shot will work in case of an attack, it's extremely easy for the enemy player to just blast the cliff before going in. Not to mention that these cliffs are inherently biased towards Protoss and Terran with Zerg having a lack of T1 ranged units.
The destructable bush seems like an interesting idea, though I'm not sure if the respawn thingie is good or bad. Without the respawn, they are simply baby variants of regular destructable rocks, which could make for some interesting earlygame gameplay. With the respawn, they might interfere with the game too much to be worthwhile. Especially at high level play you kind of need to be able to check expo's with a single Zergling without needing tons of micro and hassle to do so. Regrowing bushes at expos might make risky play way too rewarding.
Regrowing bushes could be interesting in mains or near backdoors of such though, or even in the middle of the map. Maybe with a 5 minute respawn timer it could even be interesting to (partially) fill up open areas with them to allow players to decide whether they want an open or a closer battlefield (i.e. Zerg would want to use some units to snipe the bushes before going in in order to flank correctly).
You point out some interesting points on the destructible bush. Yea, it seems a bit annoying, but I thought it could greatly change gameplay in some areas and make it interesting. For example, you want to check out an expansion, but you have to destroy the bushes in the way first, but in an interesting situation, a protoss player might just snipe 1 bush and block an army of lings from getting through with just a few zealots. It has potential to be just as or more interesting than the original destructible rock itself. I'll admit, it was the best idea of all of them and most of the others are plain trash, but might have a chance somewhere to be used quite well.
I don't have any other ideas at the moment, I'm currently working on some melee maps for once. :)