First set's AC said:
If you wish to run a little more Special Attack, you can lower Kyurem's Speed EVs to 216 for Adamant Lucario or 224 for Adamant Landorus-T.
Remove this part, it's trivial info, and besides you should never do it because you don't gain anything significant with a mere 20 more EVs on SpA.
When talking about using Dragon Pulse + Focus Blast, mention some of the targets that Focus Blast hits harder than any of the main set's moves, such as Ferrothorn and Tyranitar, as well as some popular targets of Dragon Pulse, such as Starmie, Keldeo, and Politoed.
Remove the mention of HP Fire from the AC of the first set. It is too niche, being useful only to OHKO Scizor, because Ferrothorn loses anyway as you explained. If you want to mention it somewhere, do it it in the OO (specifically for the first set i mean not as a move in general).
First set's AC said:
If not using Tentacruel, you should consider another Rapid Spin user such as Starmie.
Why? Mention specifically why Starmie works good with Kyurem, aside from Rapid Spin support.
First set's AC said:
Politoed can also make a good teammate, since Kyurem helps beat other rain teams and enjoys stalling out Ferrothorn, which many rain teams struggle to KO.
Why is the help to beat opposing rain teams needed? This sentence implies that rain teams have problems against other rain teams, which is both a really vague and weird thing to imply. I would remove it altogether.
On the offensive set you mentioned partners to lure and cripple the blobs but not partners to straight up deal with them (as in Pokemon that are able to switch into them and beat them) so add some of those.
OO said:
Outrage, Dragon Claw, Dragon Tail, Zen Headbutt, and Stone Edge
Remove any move which is not worth using at all from this list. OO is not the place to list the physical moves that Kyurem gets, just those that have very small use.
OO said:
A bulky set with Substitute, Hone Claws, Protect, and either Dragon Claw or Dragon Tail is fairly notable as it can easily dispatch Chansey and Blissey, and can wear other problematic opponents down with residual damage. However, these are almost completely outclassed by Kyurem-B, so there is little reason to use them.
Why Protect and not Roost? Also, you say that there is little reason to use it but don't actually mention what this reason is, so please do (i assume the only one is Pressure).
Finally, please organize your checks and counters section so that you mention the Pokemon there in order of how well they deal with Kyurem. For example, Chansey and Blissey should be at the top of this section, as they are the best counters to Kyurem.