At the end of the day, Blizzard, and Thunder will be viable options. Similar to Groudon’s Solar Beam, they will hit hard even if the Quick Move isn’t the same type.
Plus, Kyogre has better survivability than Gyarados, and Milotic. A much higher Attack helps its Waterfall deal notable damage, and it will get charged up for the Blizzard.
Mamoswine with be good for the Lati with Thunder, and Kyogre for the Hydro Pump Salamence, etc.
Kyogre, I think, is so good that even not having a Dragon Tail Quick Move won’t prevent it from handling Dragons.
Also consider this: if we get Kyogre in a couple of weeks, and Gen 4 doesn’t get released for about a year (and if they slow the release per batch like with Gen 3), then we would have been able to power up our Kyogre’s by then, and it won’t be as expected for someone to try and evolve their Piloswine. It may be nice, but if one can wait for Mamoswine, and we don’t know what moves it will have (Kyogre shows that in-game “confirmation” data can be switched out), plus based on demand moves can change - look what happened to Blaziken once people complained it didn’t have a Fighting move, they changed it within the first day of release.
I.e. I maxed out my 100% Vaporeon, no need for a Milotic, even if Milotic has Dragon Tail, etc.