What team can I build?

As far as I can see, most of your servants are fairly selfish/independent damage servants. If you have Hans you could maybe put him with zerkalot and Medea lily, but honestly I'd say you'd be better off grabbing 2 good DPS servants (your pick, most of what you have is pretty good) and just putting them with a support list Waver. I can't say I see much synergy between the servants that you do have.

That's a good farming team you got there.

Farming servant:
- Nikola (good againts servant + saber mob)
- Mordred / Salter (Farm Lancer enemy)
- Da vinci
- Lancelot (serk)

Nuke Servant:
- Nikola (Crit Nuke + NP spam)
- Rama (Nuke Divine enemy + Lancer enemy)
- Herc (Equal to 5* if you grail him to 90/100)

You can just put Herc + (other offensive servant) + friend Waver.

Train your bronzies. Hans, Georgios and Mash are FGO's starter pack. They are like salt and water for cooking dinner or like the explosives for a muslim.

Hans+Mash is a pretty solid staple, you can also run Medea Lily with Mash for hard content if you want more healing...but Hans is better for damage. Andersen is the resident crit-support, you want to run him with people like Lancelot or Emiya.

Georgios is pretty good too, he makes sure that your damage dealer remains alive, he protecc just like Mash but he does it for 3-turns and he can be really tanky. When he dies, Mash comes in...It's good stuff.

If you are not impressed, there's a video you should check: https://www.youtube.com/watch?v=YqVVUVMh0R0

For farming it really comes down to Kaleidoscope. Lancelot loves that.

You can build strongest arts team : Da vinci + Morzart + Shakespeare

I think you can greatly benefit from a stargen like hans, hassan, and fuuma.