If Illusions was being considered for banning, then logic would dictate that Donate is the real problem, since Illusions and all the other cards that we've been asking "WTF?" about when they got printed (Carnival of Souls, Thought Lash) suck just as bad as they did before, unless of course you can Donate them. Thus, Illusions is not and never was the problem.
Donate and Necro should both have been seriously considered, and I believe they were, but really, Donate is not a broken card by any means. Necro is, by comparison.
I think the choice to ban Ritual instead of Necro makes sense from a certain point of view. Banning Necro would obliterate several deck types. Banning Ritual just slows them down and gives decks that can beat Necro-Pebbles and Necro-Donate, etc (and those decks do exist) the time they need to compete with the otherwise blazing speed of the Ritual-Necro open.
Being a dedicated Suicide Black player and hatred player this last season, the only thing I'll be losing, again, is the blazing speed. First turn Negator and/or 2nd-turn Hatred kill don't happen anymore, and I am glad, ironic as it may seem. Suicide black only loses about a turn, maybe two, in speed, and that hardly cripples it. This Arena season, the winner (with about 80% more points than the 2nd-place guy) played Speed Black the whole season. No one could stop him (none of us played Trix or Pebbles, btw) because his sideboard destroyed anything that could have competed otherwise. White (weenie and Replenish)players lost to first-turn Glooms/2nd-3rd turn double-Glooms, Green was hopeless anyway, but the ability to set up Deathgrip and Perish backup by turn 2 sealed that fate. There was nothing fast enough, and it was Dark Ritual that was the problem.
I myself had to stop playing Hatred as much because nobody wanted to play me (except the burn-guy, for some reason) as no one was having much fun, after the 1st week, seeing my 2nd or 3rd turn Ritual/Ritual/pay 18 life kills, not even me.
I see the various points of view, and I myself question the wisdom of leaving Necro alone, but banning Ritual was not wrong, in my opinion. Everyone's screaming "Black is Dead!" but it's not. And is no more 1st-turn Negator a bad thing? It's only in Extended anyhow; Swamp-Ritual-Negator open will be around in Standard until the Fall. Will Ritual be printed in Invasion? I don't know. I hope so, but if not, the black Shock will turn up sooner or later, and people will use it as if Ritual had never existed.
Enough ranting, I'm going to bed...