I usually run 4 SoSe because it doesn't compromise speed all that much. 6 of 'em really changes the game because you can either rely on them to give you CC or offence. The latter is much more reliable, and therefore 6 SoSe force me to pack 2 copies of all essential control cards:
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The two alternative builds I use sometimes are flying Pulvies (and EE's) and SoFo+GF+BW.
8 QT's is something I arrived at a long time ago for 6 SoSe decks. It consistently lets me play Dragons quickly enough that they actually become impactful cards. Steamie is the best grower of them all by far but can be replaced by faster CC like Thunderbolt or Purify since you want to go up against Plat. Mirror Shield is a viable option against Gold.
Wings base is another viable option, more so for Gold than Plat but certainly works for both:
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The increased speed is sort of just more fun to play with and might make it more lucrative for electrum/h.