I'm not sure i understand the complete idea behind this. All the consequences you mentioned can also be achieved without having the roid split up immediately:
Cherry picking: We can -- and i'm not sure if we are -- de-spawn the roid once it has been opened and stuff removed from it after a certain time, so the trash despawns after a while and is replaced
We can turn every roid into a potential poprock. Actually they are, but if you are asking us to also remove the visual cues, well people might get angry a bit and rightfully so
There are however a bunch of issues/questions related to this:
Like Arthur already mentioned, the proliferation of objects in space -- especially movable ones -- is not a good thing and would increase our network and server load significantly. Also the client is not very efficient with many objects it would seem. There are unfortunately a bunch of algorithms whose complexity is increasing with the second power of the number of visible objects --> bad
How do we assign XP in this model. Does the guy destroying the asteroid get it --> people will just pop the roids and leave everything floating for XP --> see problem 1. Do we give it to the guy picking up the ore --> power leveling
This is less of a problem, because it already is a slight issue now, but it would be made worse by this: If there is a nice device in the roid, it is now floating in space and whoever put it there spent time and energy to remove it. Anyone can swoop in and pick it up though, putting the original miner at a disadvantage.
Imho this would cause more harm than good, but like i said, maybe i'm missing something.
Regarding mission items: I guess technically we could put mission items into roids that are only visible and collectible by the guy on the mission, similar to how WOW and other games are doing it. Problem is that this would mean a significant re-write of the inventory subsystem. I'm also not sure i this is really wanted. Quite often i read that people here enjoy the aspect that not everything is handed to them for free. Maybe we could code in a hardcore mode with permadeath and everything that players can chose :)
Btw, typing out a post like this takes me between 30 and 45 mins. I'm doing it now, because i'm on vacation and need some distraction from coding. In general this would be shortened to "won't work" or no answer at all, because that time is better spent working on the code. Also it unfortunately sounds quite rude sometimes, because of the brevity, but is not meant that way. We really do think about your suggestions and take them into consideration. It's just that very often they are either unfeasible like this, or are asking for things that are throwing off the balance of the game (whatever that means) with the hint that it could be made very very rare sometimes.
Hope that explains a few things.