Art team

Wouldn't recommend running this team since you have no main offensive damage dealer, so unless you want to take forever to just clear 1 mission then no I would recommend for a basic arts team just switch out Mozart for robin hood.

Those 3 are all support servants. Ideally, you want 2 supports and a main DPS. With a setup like yours, I imagine you'd have some trouble dealing damage (Mozart might help with that a bit, but still). Also, 2 of those are 2* and below with the requisite low health, so I question that team's survivability, especially since none of them have a hard defensive skill (ie, dodge, invincibility). Waver's Defence up might be good for a while, but your servant lineup is still too squishy overall imo.

Also, Hans is mainly a crit-support, and with 3 casters, I don't think criticals would be much of a priority for you, so you'd be better off replacing him with an arts damage dealer like Vlad or saberlot. Similarly, you could replace Mozart (arts support) with a crit servant like Ozy, Kintoki rider (or Saberlot for an arts/crit comp) to make use of Hans's crit buffs. Lastly, Tamamo is typically considered a better arts support than Waver, but this is minor. If you don't have her or a good arts DPS, just stick with Waver and you'll likely be fine.

Another servant you might want to try is David. His NP is buster, but he does have 3 arts cards, and more importantly, a party-wide dodge, which would add to your party's stayng power.

You need at least an offensive servant. Running a full support team is just waiting for you to die.

I would suggest Medea, Robin Hood or Euryale. All of them perform well in quick teams, but Robin Hood and Euryale would be better since they can appreciate the stars from Mozart and Andersen due to their Archer star weight for more reliable crits.

The others are right. You should have one arts dps and 2 supports. Keep Mozart in the back line though and get plug suit. Switch him in when a perfect storm happens. Meaning your main dps has their NP up and two cards for an EXTRA chain or whatever other combination you deem worthy and pop Mozarts arts booster and star gen skill. Stick that welfare CE on him that Grant's 20 extra stars upon entering the field too if you want to go over the top