1-3 stars worth raising?

Hans for sure and David should be pretty useful.

Euryale for fights with male saber/zercs.

Hans, best support.

Kotarou or Hassan Cursed Arm, for amazing stargen.

Medea, David, sir bedever, mash, kojirou, fuuma, Robin hood, von hohenheim, Medusa

I have others leveled, but those are the ones I use most. Sometimes for a particular skill, sometimes because the event CE's and too expensive to field gold servants.

Most 3-star archers are broken (Euryale, David, and Robin). But would raise Euryale first. When facing male servants, she outperforms even most 5-star archers.

Hans, budget Waver.

Bedivere, super strong ST NP. But good luck in getting him to NP5. I think you cannot get him from FP summon (I never got).

Medea and Lu Bu are good at certain scenarios, not as good as the above in general.

Saint George and leonidas for taunting.

And of course Arash, king of farming.

Majorly lowstar servants have good kit already. Just avoid Benkei, Gilles brother, Mephisto, Geronimo and Phantom they really hard to use. This servant need a lot of experience, perseverance and also wits to use them.

For example that Gilles saber it's not a saber, he is a '' berserker '' with the right support and hard thinking brain can dish out a lot of damage to all job except Archer. He has Buster Buff with no CD at lvl 10.
The only saber with Madness Enhancement EX in FGO is Saber Gilles.

With Mozart already maxed you can use and raise other 1-3 star Art servants as well.
Like Mashu, Georgios, Robin hood, Euryale, David, Paracelsus, Hans, Medea, and Hassan of Serenity.

For Boss killing a team of Paracelsus, Mozart, Robin with Friend support can melt neutral enemy and obliterate Saber and berserker with ease. Just change Robin to Euryale if the enemy mainly have male servant. Just don't use them against Lancer.

For farm Arash, Eric, Spartacus is the best at their job.

Hans is fantastic and if you've unlocked Bedivere from the story, he's a great ST Buster servant as well. Mash for sure if you haven't already.

Personally, I'm partial to Georgios for defense, taunting, and as a future combo with Siegfried once he gets his skill strengthening. He's not as good as Mash for defense against AoE noble phantasms but his 3 turn taunt and battle continuation can save your team against multiple ST NPs.

Ushikwakamaru is also great for ST damage and she's got decent team support with an AoE attack and NP gain buff. If you didn't get Kintoki (Rider) she's the next best thing.

Saber-Bedivere and Caesar
Lancer- Proto Cu is a good investment but not required since you have reg Cu
Archer- Arash, David, Robin Hood, Euryale
Rider-St. George, Ushiwakamaru
Caster- Hans, Shakespeare, Medea
Assassin- Fuuma, Hassan of the Cursed Arm, Sasaki
Berserker- Lu Bu, Kiyohime

Nearly all of the 3*s are worth using in my experience with the F2P servants. There's a few oddballs that you might want to look out for, but for the most part all 3* are viable and are effective in their roles. I don't feel the need to talk about them, but I will go in-depth about some of the 1-2* servants.

Hans, Shakespeare, and Wolfgang Amadeus Mozart are all worth using. They have nearly unrivaled utility and all will be of some help both now and in the future.

Arash is a nice farmer and a great kill n' switch. A must have for most challenging quests and singularities. (See Also: Camelot)

Leonidas and Georgios are great tanks capable of redirecting damage entirely away from your DPS, and both fulfill different roles. Benkei might also be useful for this role as well. Regardless, it might not be a bad idea to have all three sufficiently leveled along with Mash.

I think I've answered most questions for 1-2* servants. The rest is just up to you. Use whoever you like. Unless they're in the COOOOL tier, they shouldn't really let you down, and even so, you can try to build a team around the COOOOL tier units and make it work if you like the characters enough.

Nobody can really give you a good answer without knowing which other servants you already have.

But if you don't currently have Waver, then you should definitely build Hans. He'd be top priority, imo.

Otherwise, for farming, Arash and Spartacus can be nice.

For certain content, Euryale can be good.

If you don't have a Saber, then Caesar is pretty good. If you don't have a rider, then Ushiwakamaru is good. Medea is alright if you need an offensive ST caster, or a buff stripper.

These servants are very good generally and typically perform well under a variety of circumstances:
- Hans - Universal support (Budget Waver)
- Euryale - anti-male nuking and stall
- Robin Hood - massive nuking
- David - Party-wide dodge and healing
- Medea - Buff removal and NP spam
- Fuuma - Generating stars
- Bedivere - Massive NP damage at NP5
- Caesar - Decent support/utility options on a 3* saber
- Ushiwakamaru - Like Caesar above, decent kit on a 3* rider
- Lu Bu - Damage bursting
- Arash and Sparticus - AOE NP with NP gain, good for farming
- Shakespeare - Mozart buster equivalent, and also charges NP where Mozart gives stars.

These servants occupy specific niches, but ones that aren't as easy to use as those above:
- Georgios/Leonidas - Excellent tanks
- Billy the Kid - Burst crit DPS
- Asterios - Debuffing