I did some basic research and found the following:
Useful abilities:- Unburden- Quick Feet- Speed Boost- Surge Surfer- Weak Armor
Weather-based abilities:- Swift Swim- Chlorophyll- Sand Rush- Slush Rush
Mostly useless abilities:- Motor Drive- Steadfast- Steam Engine- Moody
Priority increasing abilities:- Gale Wings- Prankster
Are there any other abilities that increase speed under some circumstances?
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Abilities that can raise the speed stat stage (bold indicates the ones you have missed out):
Beast BoostMoodyMotor DriveRattledSpeed BoostSteadfastSteam EngineWeak Armor
Source
Abilities that raise the speed itself (hence can stack with stat stages):
ChlorophyllSwift SwimSand RushSlush RushQuick FeetUnburdenSurge Surfer
Source
Gale Wings, Prankster and Triage increase the move’s priority, but do not affect the bearer’s speed itself.Source