Hi there i am glad you are using hail!
ok now on to the rate for a team based on stall tactics you have NO DRAGON RESISTS! this hinders your team alot with many powerful dragon types in OU. Now i know you have a few ice moves that can threaten them but you have nothing to take a hit. you also have two fire weaknesses and only 1 resist which isnt enough in my opinion. Also stealth rock is mandatory if you dont want your team eaten up by Volcarona and even if your opponent doesnt have volcarona stealth rocks is arguably the most important move in the entire metagame. for these three reasons i reccomend changing Reuniculus for a spiecally defensive heatran
Heatran @air baloon/Leftovers
252hp/252 SpD/ 4 spe
This is the set you want air ballon or leftovers is up to you as leftovers prevents you from getting worn out by hail dmage where as air baloon gives you more oppurtunities to enter a battle and set up stealthrock(i use air baloon on this heatran set in my hail team but it is up to you) I chose lava plume over fire blast because of the 30% burn rate earthpower is just for coverage and roar is for phazing. Heatran will help you alot against sun giving you a powerful poke in sun a volcarona check and a poke that gives you stealth rock support. Heatran shall replace Reuniculus as Trick room isnt doing to much for your team as it basically makes Cloysters shell smash useless.
you also have 3 rock weaknesses and no resists A Bulk Up Conkledurr
can help. I would suggest swapping gliscor for conk although you lose some stalling ability conkledurrs power can surely help weaken a team and make it safe for Cloyster to sweep.
120 HP / 252 Atk / 136 SpD (o spe ivs)
Conkeldurr also acts as a status absorber and the 0 spe ivs are to abuse payback more effectivly and the loss of speed isnt to bad with conks low base speed (45) and acces to mach punch
I dont understand why you have moves slashed (/) Froslass wants Blizzard because of hail and Cloyster wnats razor shell due to stab and coverage. Abomasnow wants his Physical attacker set because it is by far the best abomasnow set trust me I use it Delko uses it and majority of good hail players use it.
188 HP / 252 Atk / 68 Spe
Max attack makes Ice shard and wood hammer do crazy damage to politoed, Tyranitar and dragons respectivly where as leech seed+protect help with stalling and hp recovery as well as scouting.
I hope i helped you with your team and i wish you luck in creating a nice hail team!