I think all these things have already been discussed more or less... Here's how I've understood it:
1. Mines are planned
2. Although this could be useful for stealthy actions, it's considered as a bit useless (I also think it wouldn't be so simple to implement)
3. Dark areas/nights where you have to use flashlights or other light sources would be cool, but the engine of rwr could not master it (right now

)
4. Explosions (and also destroyable terrain) are also great additions to the game, but very hard to implement (that means no implementation before ver. 1.0)
As the devs would say now: "Great suggestions but we have to focus on many other things first"

(but of course they are right). If there are some things which I missunderstood I really apologize that...