Spell Damage +2 or more on something with less than 9 mana so you don't have to wait until the game has definitely been decided to use it.

I would like to see Blizzard borrow some design ideas from the game "Dominion" a little more. "Gang Up" feels a lot like a dominion card.

Some of the following is a bit sloppy in the way I've worded the stuff, but I think some of the mechanics could provide for some interesting gameplay:

- Deathrattle (or battlecry): Shuffle 2 of this into your deck.
- Rebound: This spell casts again at the start of your next turn, but without rebound.
- A really terrible card (possibly even detrimental) that when it is played, or dies, a much better card (that cannot normally be in a deck) is added to your hand.

the ability to scroll through the plays and not just see the last recent ones on the left side

Battlecry: Target minion permanently counts as a beast.

Minions with activated abilities maybe?

Something like:

3 mana to play - 1/5 stats

Click to activate: pay 2 mana, deal one damage to target creature.

?

ability to use hero: doge