A sad topic for today. Mark/dash is a bit in a sad spot for many people at the moment - but I see where rot was going with this. Melee champs, especially burst heavy ones with little tank, suffered greatly in ARAM because of the incredible focus at distance. 
Rengar, for example, won't be able to build up his damage and leap atop unsuspecting victims from the brush like he wants to... sorry kitty! 
in Aram, Rengar should build to be a resistant, more tanky version of the Rengar he was supposed to be in order to win the game... but that only takes the cat nip out of his pan and expects him to preform just as good. Now that he can't gank anyone, because - you know - 1 lane and all, he can't pick off enemies, and if he dives in, he's going to be toasted before he can do any real damage - harming his team by putting them in a 4v5. The only way you can play him in ARAM is by sitting back, throwing Bolas at close by enemies and waiting for the enemy team to slip up so that you can counter-engage and sweep up a kill or two to make it a 4/3v5. That meant that everyone with Rengar would be sad, because they knew that they had to just stay back and wait in order to help their team... and in most cases, they'd be helpless as ranged champions poke them down without any threat of counter-play... and that's not cool, bro.
So I can see where Mark/Dash came in. They wanted Melee champions to not be so sad in ARAM. They wanted champions like Braum 
, Jarvan 
, and Singed 
to actually be solid champions to play with in the game mode. Braum may have his ult up, but he has to wait for an enemy to jump in before he can use it effectively... not anymore, he can mark/dash in and use that ult to help his team and not feel so sad! Jarvan no longer has to sit back and stab at his enemies, throwing flags and trying to hit the enemy from afar as he gets bursted down by volleys of enemy poke, he can mark/dash in and cataclysm the enemy team, doing something useful without having to wait for the enemies to mess up.
No longer will singed be sitting in a cloud of his own poison, flicking puddles of glue at the enemy after running in and being melted time and time again - inducing nothing but rage and hatred from his companions and not helping one bit. Now he can Mark/dash in! And even if he doesn't survive the focus of the enemy team, he can deal enough damage and cause enough chaos to open them up to his teammates, letting them take the win!
A good idea in concept: give the champions of the abyss a gap closer so that they can make some nice plays and feel useful for once. Tryndamere will actually be useful in aram! Yay! 
But it's not all sunshine and rainbows, sadly, they didn't turn the abyss into candy-land and make the poros crap rainbows and sing poetry. No, the mark/dash was taken because it was a beef-ball in and of itself.
They put damage on the snowball because it wouldn't be so fun to use without damage, wouldn't it? But then it became like a sniper-ignite. Dealing a considerable amount of damage for having such a shot cooldown and such a wicked range. Even with the damage nerfed, that's not the point, If stabbing someone in the face with Garen's sword deals 97 damage + armor. A snowball to the face shouldn't deal 30 outright. 3 snowballs shouldn't match a huge sword! 
and I don't care what Nunu says! 
Aside from that, you still have the true sight. I understand that this can be useful for seeing what you're getting into. it IS critical knowing of you're about to dash-ult onto their low health LeBlanc 
and not their tanky Gallio 
but it's still too much. Teemo may be annoying, but seeing him in stealth makes it so much easier to counter-play him that it's almost useless 
.
A true story: I was playing ARAM the other day and had the incredible fortune of being Shaco. 
The lovely clown is very useful at creating chaos for the enemy... but I was stealthed from my Q and was about to close in on their low health Katarina
. I was completely separate from my team, so even if she jumps in - it wont be on me! But then, their Allistar 
hits me with a snowball. Even when stealthed, they can see me! Kat jumps me instantly, and then Ali slams me into a wall for good measure. Needless to say, I got melted. The snowball shouldn't destroy gameplay aspects inherent to certain champions when it's designed to do something completely different.
The concept of the gap closer is solid, a good idea to get gap closing champions into the fray. But now ranged champions are using it! I saw a Ziggs dash under a turret, throw down some of those slowing bomb things, then throw his W down beneath him to launch himself out of range - and also knock an enemy into the mines and kill them. Good play, mind you, but it's ZIGGS
he doesn't need any help in ARAM! He's already the ARAM king!
Should The snowball of love be taken out of ARAM? I don't think so, personally. But with the on hit / dash to damage, the true sight and the ridiculously low cooldown. dramatic inhale it's just not what the game mode needs to be balanced. I think that it would be a far less as extraordinary problem if they just winded up the Cooldown so that you can only throw one every 50 seconds or so, rather than every 20 seconds. If they did that and got rid of the damage aspect, and didn't grant vision to units hit - but rather put a snowflake over their head so if they ARE visible then you know who you're diving.
If you can't get rid of it. Fix it. 
and then rerolling twice to get 
is just the definition of fun, especially when you're playing against 
