Ice types are generally the most ignored Pokemon. Even in OU play, which is rife with Dragons, about 90% of the time players will just use Ice Beam on their Water type or something, because with Stealth Rock flying around, Fighting moves being prominent, and Fire being a great offensive type, Ice just cannot support itself.
The only Ice types that really see any play:
Mamoswine - this thing has an almost unresisted STAB combination, it's also generally a great anti-metagame Pokemon
Cloyster - this thing only sees play due to having Shell Smash, Skill Link and the equivalant of a 125bp Ice move, and a 125bp Rock move. I can guarantee you it would be UU at most if it didn't have Shell Smash.
Black Kyurem - This thing has monstrous attack. An Outrage from Kyurem-B is gonna dent whatever it hits, if not directly OHKOing it. However it does have its flaws; it has a great attack stat, but not that many physical attacks with which to utilize it. It's also forced to go mixed if it wants to use both Fusion Bolt and an Ice move on the same set.
White Kyurem - This is just a murderer. Unlike it's brother, Kyurem-W has all the tools it needs for destruction. Fusion Flare is great coverage, it has Ice Beam/Blizzard, and then it's Draco Meteor is something out of this world.
(shoutout to Weavile, who I think went OU in D/P/Pt metagame, but those days are gone)
There are 5 simple steps to make Ice better:
1 - Remove it's weakness to Steel
2 - Give it SE damage to Steel (cold steel is brittle)
3 - Remove its weakness to Rock
3 - Give it a resistance to Dragon
4 - Give it a resistance to Ground
There you go, actual Ice types now have some form of defense against other Pokemon. It's still weak to Fire and Fighting, but I wanted to remove 2 weakness and those 2 seemed the best to keep.