It is wise for cards to have a low enough cost to be played before killed by a rush deck. 10 elemental quanta is high enough.
Punishing players for choosing Aether as their element of choice is Elemental Hate. Color Hate has had a net negative effect for Magic the Gathering.
I'm not sure if comparing to Magic is quite fair, but if we were to, I'd say that the net negative (and reason I stopped playing years ago) lies in having too many cruddy, slapped together cards, not from any specific colour hate. Various "protection from" mechanics kept the game fresh, and provided answers to the more commonly used OP rares in any tournament metagame. Also, in that other game, there are only 5 colours (plus other) - for any one colour, there are 2 others that you're built to hate.
This idea hit me when facing (yet another) Chrysora/Arsenic build in the Arena. If a Silence effect is too hate-y (it's a word now, darn it!), what about just using the natural counters each Element's theme suggests?
Dawn - Vampiric abilities do you no damage/
Dusk -(insert idea here -
is kinda weak already);
Vaccine - You and all your creatures are immune to further Poisoning/
Deadly Bonds - Opponent gets 1 Poison counter for every creature he has in play;
etc.
I notice that my first posted conceptualization of this hit at least 2 of your hot-buttons (Elemental hate; Lockdown). Do you think that revamping the idea in this way would be more acceptable? After all, if nothing else, it would add to the metagame (players would have to de-focus their decks a little - a Poisonstall would have to pack at least a few creatures, just in case of Vaccine).
Or, perhaps, I should just scrap it - or throw it into the "Steal My Idea" thread, for better minds to chew on?