Dodrio is one of the better options in FRLG, but it's still outclassed by Clefable and Snorlax because of its multiple weaknesses, low special defense, and shallow movepool.
Dodrio
Availability: Mid-game (Route 16, levels 18, 20, or 22).
Typing: Flying / Normal is pretty good, as it is super effective against Erika, only weak to Lorelei's Ice-types, and neutral elsewhere.
Stats: Dodrio is a glass canon, boasting great power and Speed but it's fairly frail. Most of the time, when it can't OHKO, it won't last long.
Movepool: Dodrio should be taught Fly immediatly when caught. Doduo gets Tri-Attack by level, which is a good STAB option until Return through TMs becomes more powerful.. It also learns Drill Peck at level 47, a strong STAB that helps against Bruno and Agatha.
Major Battles: Dodrio wins easily against Erika and Sabrina and performs greatly versus Agatha. While it won't sweep, it still performs quite well in other major fights, being able to take down a few Pokemon, like Bruno's Fighting-types, before fainting. Lorelei and Lance are the only matchup where Dodrio doesn't perform well (outside of KOing Jynx and Dragonair), because their Pokemon are bulky and will take down Dodrio easily with super effective or powerful moves.
Additional Comments: Doduo is a solid Pokemon to use and performs well most of the time. It's very self-sufficient in terms of TMs, as only the Return TM can prove to be useful and, even then, it isn't obligatory to use it.
Clefable
Availability: Early-game (Mt. Moon (B2F), level 10 or 12).
Typing: Pure Normal type gives Clefairy a neutral matchup against every important Trainer save for Agatha's Ghost-types and Bruno's Fighting-types.
Stats: Clefable has balanced stats all around, with particularly good HP, Special Attack, and Special Defense.
Movepool: Clefable gets by with Pound for Mt. Moon until the Mega Kick tutor from Route 4 and the Secret Power TM from Route 25 for a more reliable STAB. Later on, this STAB can be upgraded to Strength via HM. Clefable has a lot of coverage options through TMs, namely Water Pulse, Thunderbolt, Ice Beam, Psychic, and Calm Mind, among others.
Major Battles: Secret Power + Mega Kick 2HKO Misty's Starmie, but potential confusion from Water Pulse can be annoying. Secret Power handles Lt. Surge fine, and, if you give Clefable Psychic, it handles both Erika and Koga well. Clefable is unlikely to sweep Sabrina and Blaine, but beats Giovanni at Viridian Gym with only one healing item assuming you have Water Pulse and Psychic. Despite having Calm Mind, Clefable noticeably takes a hit in effectiveness at the Pokemon League thanks to both its comparatively lower stats and the level gap, though this can be remedied somewhat with healing.
Additional Comments: Clefable is a great versatile Pokemon that is only held back by Clefairy's rarity and requiring healing in the endgame to perform well. Clefairy can evolve almost immediately with the Moon Stone available at Mt. Moon. Clefairy can learn Sing at level 9 before evolving if desired.
Snorlax
Availability: Mid-game (Route 12/16, after obtaining Poke Flute, level 30).
Typing: Normal makes Snorlax neutral in most matchups, save for Bruno, who can hit it super effectively.
Stats: Snorlax possesses a great Attack and bulk, with its high HP compensating for the below-average Defense. However, it has poor Speed and below-average Special Attack.
Movepool: Snorlax learns Body Slam at level 33 and can be taught Hyper Beam for an incredibly powerful STAB move. Surf via HM provides coverage against Rock-types. Yawn is useful for consistently putting foes to sleep.
Major Battles: Snorlax easily sweeps Erika, Koga, Sabrina, and Blaine, as well as Giovanni with healing. It is decent against rival fights, Lorelei, and Bruno, though it is unlikely to sweep any of them.
Additional Comments: Snorlax is an excellent Pokemon due to taking on many major opponents without requiring contested TMs. In addition, it comes at a high level, which compensates slightly for its Slow growth rate. Thick Fat is vastly preferred as an ability, as it improves the Blaine and Lorelei matchups.
source
source
