During a FGM, it was a cool, flavorful addition that everyone knew wasn't going to be around forever. However, like some others have said, I, too, primarily play ARAM (Not on a smurf, because I can't stand playing against the same people over and over, so I'm not going to do that myself) and as a constant spell choice, for a permanent game mode, something about it has to change if it's going to stay.
In the few games I've played since the patch I have been on both sides of a team that is able to spam the spell to ridiculousness. I just finished a game where I was berated for focusing Garen and Wukong, but they both spammed the snowball til someone on the backline got hit and then it was a free for all mad-house. And there's a lot of discussion about how it makes tanks more viable.
This is true, I've seen Ali and Gali fly into the middle of an entire team to initiate, but the problem is many tanks/bruisers/fighters are meant not to just soak up damage but soften and set up teams for team fights. And they could already do that before. I've flashed as Galio, I've WQ'ed with Alistar, heck I even somehow went positive in my first ARAM as Udyr. But part of the success, I believe, is that you have to do the best with what team you're given.
When a Nunu takes out half the OP team cuz they were overconfident and face-checked the brush, he did it without an infinitely long dash. When a Galio, or Wukong, or [insert melee tank/bruiser here] waits at the front line, soaking up a little damage here and there waiting for their time to strike, they do it by strategizing with their team. Udyr, Skarner, all of them the same way.
Take that as you will, whether it has merit or I'm just a noob with no credentials (i know match histories and levels will be checked), but while not every team will be setup perfectly, with ARAM there is a good chance that some number of champs on either side will be able to use the distance and the dive potential abusively.
Plus, with the spell as is, it becomes much more prone to abuse once a team gets ahead. A team that's lacking a tower, for example, is less profitable with the mark/dash than the team that took it, since typically that would be suicide to jump into them (not saying certain games don't warrant it; everyone loves a turn around) but the winning team has a MUCH longer engage now once the tower is down and gets a much greater benefit to spamming the snowball.
Longer cooldown, shorter distance; I don't know the proper way to fix it. But I feel that assassin's getting twice their normal engage and tanks being able to immediately lock down backlines from that distance needs more "counterplay" (not sure how I feel about that word) than just "Dodge it..." While it may not do the damage that Nid spears do, it's ARAM, eventually someone is going to get hit, and best case scenario, assuming you have a tank, is that they take all of them that do hit.
I'm not going to say that I won't play LoL anymore, I've played it all day long today despite these feelings. But there's a pretty definitive split, it seems, among people who like and dislike the snowball and I'd hate to see my only game mode turn into something that's just not worth it.
That's just my two cents. (Will say though, that I'm glad to see a lot of you being pretty level headed in your discussion)