Luxray
Pros:
- Has way better offensive and defensive stats than Raichu, with Raichu's only stats being higher than it would be Speed and Sp. Def (which is a 1 point difference)
- Has an excellent ability in Intimidate, giving it even better defense
- Learns Spark and Bite very early in the game
- Obtained on one of the earliest routes in the game.
Cons
- Luxray has pretty meh coverage. Aside from egg moves, Luxray's only good coverage is Crunch at level 56 and Iron Tail through TM23.
- Lacking in Speed.
- While its Attack is greater than its Sp. Atk, its only good physical Electric moves are Spark which has such low power compared to Thunderbolt that it often deals less damage, and Wild Charge, which is learnt up until Level 80.
Raichu
Pros:
- Has a pretty good Speed stat of 110.
- Learns way better coverage than Luxray, consisting of Surf (which it can learn through TM in this generation), Brick Break, Focus Blast, Grass Knot, Iron Tail, Nasty Plot, and Dig.
- Static is an alright ability, albeit a bit luck based.
Cons:
- It takes until the 4th gym until you can get Raichu.
- Raichu is a stone evolution, meaning its movepool is mostly reliant on TMs, and you'll be stuck with a Pikachu until you either get a Thunder Stone through the Underground, or until Sunyshore City.
- Its got worse stats than Luxray, aside from Speed and Sp. Def.
Overall, I'd suggest you use Luxray. It may not have as great coverage as Raichu, but you've got 5 other team slots for STAB coverage, as well as Luxray getting good neutral coverage against most non Ground or Electric types from Thunderbolt and Iron Tail alone. Here's the moveset I'd suggest you use Luxray with.
Luxray @ Any
Ability: Intimidate
- Thunderbolt - TM24, Purchasable at Veilstone Department
- Iron Tail - TM23, Found at Iron Island
- Volt Switch - Learnt at Level 33
- Crunch - Learnt at Level 56, if you don't want to level up your Pokemon that far, you can instead use Bite or Strength as filler
