CHILDREN, AVERT YOUR EYES TO THIS UNHOLY DESECRATED PLACE!!!
Ok seriously WTF has transpired here? First some posts on running with Shiek, then some planking nonsense, I don't know where to start. Ok, how about here:
The problem is not about avoiding conflict. If you want to be a douchebag about it, you could argue that going after the opponent and trying to hit them is avoiding conflict because they cannot attack you in hitstun. The issue will NEVER be about avoiding conflict. The issue is about being in too powerful of a position/extremely limiting your opponent's options.
Take Akuma for Example. How many of you understand why he is banned? He's banned not really because he can avoid conflict, but because he takes away any worthy options your opponent has. He's so powerful that in some instances he takes away ALL options you have and you are forced to sit there and DIE. Now, you could argue that he is avoiding conflict by keeping you in one spot on purpose, not advancing towards you, but then again you can argue that he is initiating conflict because he is attacking you with fireballs. The problem is that he is attacking you, and you have no options to deal with it, no matter what.
Now, for Brawl. Running away will NEVER/SHOULD NEVER be banned. Unless by running away, you are putting yourself in a position that is obviously too powerful, then there is no need to try and impose anything on it. Think about it: is Circle Camping banned? Seriously, think about that one for a second. In most scenarios where Circle camping is seen as an issue, what happens? The stage in question is banned.
Look at Hyrule (obvious Circle Camp map, along with other problems but that is besides the point). We saw/know how bad circle camping is there. What happened once people realized this? Did we say "Hey, you can play on Hyrule, but don't run around like that" or did we say "Hey, let's not play on this stage, this could be a problem".
Circle camping in itself is not seen as a strategy that is too powerful on its own, otherwise we would have a rule saying that you cannot circle camp/run like that (in the SBR ruleset, it says you can run/camp for better position. Most people interpret that as camping/running away is allowed). However on certain stages, it is deemed that gameplay would degenerate enough that circle camping would then become too powerful.
If you have a strategy that you think is too good, it needs to pass the stage test. If it's too good on some stages, but on a fair number of other stages it doesn't break or over centralize things, then most likely it's not bannable. You can say what you want about MK's planking, but Shiek's "running away" CERTAINLY is not a bannable/DQable offense/strategy to use. If you are thinking about DQing someone for something like that, you need to reevaluate your perception on what is broken or not, or you need to start banning a LOT of things that are worse than that.
Now some things obviously fall into gray areas. Planking/Scrooging/similar things are not clear cut, and I am not fussing at anyone who takes either side on those issues. But if you seriously are thinking about DQing people for running away when we are not talking about those gray areas, then IDK what to say to you other than Wtf dude.
With that said, I think Shiek is a good "run away" character. In the air, hell no. Overall you don't need to camp in the air as Shiek. You CAN camp in the air as her, but it's hard and the benefits do not outweigh the consequences. On the ground, she is much better. You have so many tools to utilize for something like that, seriously. Dash to Shield, Crouching, Needles, fast attacks overall, not bad OOS game, etc. You also are a combo monster at lower % and getting a lead on another character is not out of the question. I think you Shiek players need to think more about getting the lead and retreating back for a second. That is quite powerful for her that I do not see used as much as it should IMO. But it's understandable, half of you might not even believe she is pretty good at such a thing.
Seriously, start thinking about that with her. And gtfo with this planking/stalling discussion, I do NOT want to write up a godly essay to **** some people.