This is a huge task. This is just a partial (and disorganized, stream-of-consciousness type) list of viable moves that would probably have to be ranked: Sucker Punch, Scald, Brave Bird, Flare Blitz, Mach Punch, Spore, Earthquake, Drain Punch, Close Combat, Moonblast, Flamethrower, Fire Blast, Thunderbolt, Ice Beam, Surf, Hydro Pump, Shadow Ball, Dark Pulse, Knock Off, Dragon Pulse, Draco Meteor, Dragon Claw, Outrage, Play Rough, Aqua Jet, Spikes, Stealth Rock, Rapid Spin, Defog, Iron Head, Flash Cannon, Lava Plume, Earth Power, Toxic, Thunder Wave, Will-o-Wisp, Sleep Powder, Taunt, Low Kick, Air Slash, Hurricane, Focus Blast, Roost, Recover, Calm Mind, Bulk Up, Swords Dance, Sticky Web, Seismic Toss, Heal Bell, Aromatherapy, Ice Shard, Icicle Crash, Icicle Spear, Rock Blast, Rock Polish, Grass Knot, Energy Ball, Giga Drain, Leaf Blade, Leaf Storm, Overheat, Psycho Boost, Quiver Dance, Dragon Dance, Shell Smash, Bug Buzz, all the usable hidden power types, Psychic, Psyshock, Baton Pass, Light Screen, Reflect, Volt Switch, U-Turn, Bullet Punch, Pursuit, X-Scissor, Extreme Speed, Fire Punch, Ice Punch, Sludge Bomb, Sludge Wave, Shadow Sneak, Poison Jab, Hyper Voice, Acrobatics, Haze, Stone Edge, Sacred Sword, Leech Seed, Return/Frustration, Dynamicpunch, Trick Room, Shadow Claw, Destiny Bond, Pain Split, Ice Fang, Flame Charge, Solar Beam, Roar, Whirlwind, Dragon Tail, High Jump Kick, Zen Headbutt, Psycho Cut, Foul Play, Slack Off, Hammer Arm, Meteor Mash, Rest, Sleep Talk, Night Slash, Aura Sphere...
Also, a lot of the reason certain moves are good is because they're used with other moves. For example, putting one coverage move on one pokemon can make a different coverage move better on another pokemon.
Are you really willing to rank ALL of those moves (plus all the ones I didn't list) based on all the ways they can interact with both other moves, other pokemon, and other moves on other pokemon?