Wouldn't be surprised if any new heroes were held back until the next expansion.
And it's not necessarily the creation of alternate heros/skins necessarily detracts/halts development of new cards/heroes anyways.
If people want to buy this junk then let them.
Heaven help a business do things to make profit.
At least as long as it stays just aesthetics.
For me personally though?
Eh... there's probably at least one character I'd seriously consider paying for once.
No idea who, but surely at least the one.
Naturally a mage and only a mage character otherwise not interested.