12 more points in speed allows you to outrun Scarf-Latios. They aren't too common, but should you ever meet one those 12 points will save its life (allows you to outrun Politoed without Tailwind, by the way).
It misses Earthquake, because enemy Heatrans and Jirachis will have much more freedom in switching - it is a bit obvious when you switch out of them. It also ensures a clean OHKO against Terrakion, especially those Scarf-Terrakions who usually beat Salamence.
Thirdly, I don't think that Draco Meteor is really needed on any other set than the wallbreaker one. It helps you with Hippodown and Jellicent as well as in dealing damage without locking yourself into Outrage too early. But both the wallbreaker and the cleaner need Earthquake to deal with certain threats, the wallbreaker additionally have to run Fire Blast to deny Forretress and Skarmory entry hazards. With such a strong 4MSS, Tailwind looks a bit out of place.
Frankly, in hindsight I don't think offensive Tailwind Salamence needs to differ itself from the offensive Dragon Dance one that much. LO-neutral-Fire Blast already has the power to deal with certain key threats so you might just use the cookie cutter spread Naughty or Naive 252/252 (Moxie). It works similar to Agi-Lucario, but with Moxie. Naive allows you a bit more freedom outside of Tailwind, since the power difference will be negligible at +1 anyway.
Salamence @ Leftovers
Trait: Moxie
EVs: 252 Atk / 252 Spd
Naive / Naughty Nature
- Tailwind
- Outrage
- Earthquake
- Fire Blast
I can offer you a bulky supporter, though you must ask yourself if Dragonite is not better suited for that role (and if Thunder Wave is not better in the long run).
Salamence @ Leftovers
Trait: Intimidate
EVs: 248 Atk / 108 Spd / 152 HP
Adamant Nature
- Tailwind
- Dragon Claw
- Earthquake
- Roost / Fire Blast / Wish
Earthquake over Fire Blast, because with Tailwind you probably aim for the guys faster than Skarmory, Ferrothorn and Scizor. Magnezone in this team is very much appreaciated. I have put one more point in HP, just in the case you cannot keep up with Roost or SR off your field.