SSR Priorities

Ozy and Tamamo are your best SSRs right now. Jeanne is also good, but doesn't reach her potential until next year and can be a bit of a pain to use before then.

Out of what you listed, Ozy doesn't really have much synergy with any of them unfortunately, his best support right now (other than Waver) is Hans Christian Anderson since they both have utility options that highly benefit each other. Merlin will be his best support when he comes out. That said, he's good enough on his own that he doesn't really need to have a specific team built around him - he's really self-sufficient with his success rate increase + Imperial privilege, and he helps any team he's in with his party-wide NP battery. Just throw him into any team to round it out I guess.

Tamamo goes well with any arts team really, and Tamamo + Jeanne + (any arts servant) is a stalling staple. Your current roster has a bit of a problem in terms of team-building potential since your buster servants are all damage dealers and your arts servants are split between support or niche damage (ie robin hood/Medea). Kuro's great though.

I don't know if you have Hans or not. You haven't mentioned him, but that's a lot of SSRs to have gotten without even getting a single copy of Hans. If you really care about team synergy (which, mind you, really isn't that important, at least at this stage) and don't have Hans, level Tamamo > Jeanne > Ozy = Shuten. If you do have him, or if you want to level based on a general idea of how good your SSRs are, then Tamamo >= Ozy > Jeanne > Shuten.

Some potential teams:
- Tamamo + Robin + Kuro for use against sabers or zerks
- Tamamo + Jeanne + Kuro/Shuten/Medea as a general-purpose arts team. Switch the final member based on class advantage, also, you can use Kuro for anything that isn't lancer.

If you have Hans:
- Ozy + Hans + Ibaraki - decent buster DPS team, put a buster-crit CE on Ozy since this team favours Ozy's crits. Use Hans as a star generator.
- Ozy + Hans + Jeanne will help Ozy with spamming(?) his NP, at the cost of not being as good with crits since Jeanne will steal stars (she can also generate them though).

Bear in mind though that class advantage usually > team comps, unless it's for harder content like challenge quests and such.

Ozy is one of the best ssr servants. I don't have him but I love his party wide np gain.
Tamamono is a great support, though I favor waver myself.

Siggy is really lackluster until his 2nd strengthening quest comes out.

Liz brave is good if you need a st np saber. Just ignore the gimmicky 3rd skill.

I like anne and mary rider, but if you have kintoki rider she is less necessary. I haven't used her much since onigashima.

Kuro is amazing and has surplanted my use of David as my primary st np archer.

My fsn cu is lvl 90 10/10/10 :-)