S Tier
- Unless you play
Leda, you might not have her, but she is a powerful Archer thanks to her stat growth and her ability to buff other Archers and nearby units. 
Nuzzuo has a strong Passive, that provides +3 attack during combat while helping against Flyers. He will also gain +10/+20 hit at levels 20 and 35. Pair this with how easily accessible Nuzzuo is, and how strong their stat growth is in HP, strength, speed, and dexterity. He can get a high critical chance as you build high dexterity.
A Tier
Peter is an option on any path where you want extra range on your Archer, as his Personal Ability grants him extra range when attacking with a bow. As he levels, he can also get extra hits. Like other Archer classes, Peter has high speed and dexterity, but low strength gain.
Inyoni is a high-attack Archer and gains 3+ strength, and as she levels, she gains even more attack and crit! She is a top-tier Archer! She is available on many different pathways. She has high strength growth, but quite low dexterity and speed. She also comes with the Bow and Infantry skills. Changing her to the Archer class is recommended, as it gives you both speed and dexterity growth to compensate for her low stats.
Lilian has a very nice ability: if her enemies cannot counterattack, she gains 10+ hits in combat. As a ranged character, enemies can't get close enough to counterattack. As she levels, she can also gain an additional attack. She has 40 speed growth and 55 dexterity, but low strength. Taking Bigrand could be an option for her for that additional strength growth, or you can go with the Archer class for the Master Ability. 
Diego is slightly later compared to some of the other characters. He has 60 dexterity, 40 strength, 45 speed and 45 HP. His Personal Ability, Caretaker, prevents adjacent allies from suffering a follow-up attack during combat. It isn’t great on ranged Archers, but the level 35 upgrade is good because it gives him 10+ hit and 10+ crit. He can also take Myrmidon for extra damage.
B Tier
Peppe’s Personal Ability isn’t very good, but it does damage to foes. However, ideally, as an Archer, you want to be the one dealing the damage! You want to deal the damage, and then the melee class finishes them off.
Jester’s Passive is relatively weak compared to some Archers, which is why he is B tier. His Passive gives +5 attack when he avoids attacks, but as an Archer you don’t really need to do that. He does have +60 speed, +45 dexterity and +40 HP.
Halvin has low strength gain, but +45 speed and +60 dexterity. Her Passive isn’t ideal, especially at levels 20 and 35.
Alternative Picks
These characters can all become Archers if you want to switch them.
Ludia's Personal Ability, Falcon, is good as it gives her extra attack speed if she attacks first.
Guzran can be run as an Archer too, as his Passive can give him +10 hit, +10 crit or +10 avo during combat, and these turn to +30 when he reaches level 35.
Mu has high speed, strength and high dexterity gain, so she can be turned into an Archer as well.
Class Preferences
Bigrand is a class preference for Archer, as it grants +15 strength and +15 HP growth. For the Archer class, you’re looking for strength and speed more than anything. Some Archers don't have much growth, so taking this lets them gain more strength as they level up.
The Myrmidon class is another option due to the Master Ability Ravaging Arts, which makes crits deal extra damage and works for any class.
The Charioteer class has decent strength, lowers your speed, but does give dexterity and defence. It could be an option for any Archers who want extra dexterity hits. However, you will rarely use the Passive.
Shido can provide extra healing when dealing critical attacks, which can prevent your Archers from dying.
Sniper is another potential class option. It has 5 strength, 10 speed and 20 dexterity. It is a common class people change to. One reason is the Master Ability that grants +15 hit when equipping a bow.
Forest Knight is another class option that provides an additional attack when equipping a bow and making a follow-up attack. This is an alternative to the Sniper class. This class offers high mobility, +5 strength, +10 speed, and +10 dexterity. It isn't as strong as Sniper, but it's a good option.
The Ranger Class is only available through the Sorcerer's Path. It is an ultra late-game class, but it is really good for Archers. Its Master Ability, Countershot, lets you counter adjacent foes during combat that are close to you (at 50%) and lets you equip 2 combat arts. It gives +5 strength, +15 dexterity, and +15 speed, similar to the Sniper class.
