You can't compare Suicune to Jellicent just because they both run shadow ball. They have different  roles and therefore one isn't inferior to the other one.
		
		
	 
Yes that is exactly what I wanted to say. I am pointing out Jellicent just because I don't want people to think that having Shadow Ball makes Suicune an inferior Jellicent.
	
		
	
	
		
		
			You could make a Suicune thread yourself(/good idea|).
Lol what?
No.
To lose to Hydreigon/Shiftry/Chesnaught instead?
Yes it Kind've does make it outclassed though.
		
		
	 
Well I am not quite sure how Suicune works if it only has 2 attacking moves since what I am using right now is 252SAtk/252+Spd CM+3 attacks Suicune and it works well for me. Due to the 
power drop of Hidden Power, Shadow Ball becomes a much better option for the coverage move.
And to be honest, with at least 2 CM up, 
Suicune beats Hydreigon even without Ice Beam if you can burn it with Scald. 
Suicune isn't a very good check against Chesnaught anyways since Ice Beam only 3HKOs 252/0 Chesnaught.
Also, I think you completely missed the point that there are 
far more checks to Suicune with Water+Ice Beam than Water+Shadow Ball. Without Shadow Ball Suicune is vulnerable against any bulky Waters, most notably Jellicent and Vaporeon, who is immune to Water-type moves and resist Ice Beam. Even 
at +6 Suicune's Ice Beam doesn't even scratch while both have recovery moves to stall out Suicune, let alone crippling it with Toxic or Will-O-Wisp.
If you have most Suicune's checks in mind, you would find that other than the 3 you mentioned in your post, 
popular pokes who are weak to Ice Beam is also weak to Shadow Ball. I have already mentioned 
Celebi and 
Trevenant in my first post. And Shadow Ball also lets you beat pokes like 
Slowbro, 
Cofagrigus and 
Jirachi much more easily.
A relatively minor point to mind is that Ice Beam suffers a power drop from 95 to 90 in this generation while Shadow Ball keeps its power in 80, which narrows the gap between them.
In retrospect, what I am trying to say is that
1) Crocune is less viable in 6th Gen UU,
2) Shadow Ball outclasses HP Electric/Grass as coverage move,
3) Shadow Ball helps Suicune beat many pokes who used to counter Water+Ice Beam Suicune, and
4) Shadow Ball can still beat certain popular pokes who lose to Ice Beam