Remove collision from allied melee and caster minions.
Keep collision on cannon, super, bannered, and enemy minions.
Now it's impossible to deny cannon minions, and probably unreasonable to try to continuously deny normal cs. The only time creep block would be a problem is if you're overwhelmed by super minions or diving their full creep wave, which makes thematic sense anyway.
http://bitspers.com/wp-content/uploads/2014/06/League-of-Legends-Red-Super-Minion.png
well he's standing inside a minion

