I'm currently planning out future summons this year and was thinking about which is more important. Is it more important to cover each of your classes, or to go after the best support servants? I'm rather lacking in the rider class, so should I aim for servants like Ozy or other strong riders if they're on rate up? Or should I aim for someone like Waver whenever he goes on rate up?
Whoever you want. However if it's for gameplay, Waver.
Waver like Merlin can make any servant better, how much better is dependent on synergy and their own potential as a servant.
Ozy is amazing though and can do massive damage and give some support at the same time.
Waver only has one rate-up next year (though unfortunately it's really close to one of Ozy's). If you are looking at improving your gameplay options, Waver is pretty much one of the only ones who can do that universally, so feel free to save for him, then spend the rest on whoever you want.
I'd go for servants who fill rolls you doesnt have, like if you lack a single target rider, aoe saber etc, rather than Waver as you can always borrow him and good as he is, I still think Hans/Mozart/Shakespeare+ a servant with class advantage/niche advantage(jack vs females, euryale vs males for example) is better than waver+ a servant without class advantge/niche advantage.
You can go for what you need OR for what you want and like, for example me, I lack in Berserkers and assassins and I'm aiming for Hokusai, got a long year to farm quartzs for her
