All of Speed's best moves are tied to Head Start, not Quickness.
You want to get Lightness, Head Start and Improved Reflexes to 50-60 and then have Quickness and Frenzied Urge at 16 or 21.
74 is the magic number to unlock most Speed moves.
Lightness is the stat that you will sink as many points into as you can.
The main issue lies with Elasticity which is a stat you want to minimize as much as possible.
The move that you need Elasticity for is primarily Jumping Twisting DDT which is a move you want and requires 74 Head Start/ Elasticity.
And to a lesser extent you also get Springboard Senton Splash and/ or Spinning Leg Drop in Grounded.
So how many points you put into Elasticity determines how many points you will put into Head Start.
The choices you should be looking at are 63/11, 61/13, 58/16 or 53/21. After you hit your magic number for Head Start,then you start boosting Quickness past 21 for DDT on Concrete, Twisting Sky Moonsault and Flying DDT on Apron.
54 Lightness
53 Head Start
52 Improved Reflexes
21 Quickness
21 Frenzied Urge
11 Elasticity
Would get you:
Standing:
Roundhouse Kick,Mule Kick,Elbow Smash
Bent:
Jumping Half Nelson Facebuster (74 Head Start/ Frenzied Urge)
Head Nelson Facebuster (73 Improved Reflexes/ Frenzied Urge)
Overdrive (73 Head Start/ Lightness)
Groggy:
Twisting DDT (74 Head Start/ Quickness)
Springboard Rolling Elbow Smash (63 Head Start/ Quickness)
Complete Shot DDT (62 Lightness/ Elasticity)
Steam Roller (61 Lightness/ Head Start)
Grounded:
Springboard Moonsault (72 Lightness/ Quickness)
Fujiwara Armbar (63 Lightness/ Frenzied Urge)
Standing Moonsault (54 Improved Reflexes/ Quickness)
Stunned:
Swanton Bomb (75 Lightness/ Improved Reflexes)
Missile Dropkick (74 Head Start/ Improved Reflexes)
Diamond Dust (69 Improved Reflexes/ Frenzied Urge)
Diving Knee Drop (63 Lightness/ Elasticity)
Plus you get the best moves in almost all of the miscellaneous positions such as Flying Forearm Smash, Tornado DDT, Rolling Wheel Kick and Running Neckbreaker. Then, boost your Head Start/ Elasticity to get the Jumping Twisting DDT, Spinning Leg Drop.
Then, boost your Quickness for Running Torando DDT and the out of the Ring moves.
Initially hit: 13 Head Start for Elbow Smash, 11 Frenzied Urge and the rest into Improved Reflexes. Later transfer your attention to Lightness.