choice scarf mew is all kinds of lame, but i'll let it slide because i've seen it in action, and its not half bad.
Set order should be:
NP > SD > Support > BP > Scarf
- The Nasty Plot is at the top because it's really hard to stop, that didn't being a thing or anything. There's no overwhelming need to run Support in this meta because Stall is uncommon. Don't get me wrong, it's still a really good set since its almost impossible to kill, and a good choice for balance teams.
- Timid 252 HP / 80 SpD / 176 Spe on Mew should be fine. The thing here is that you're outspeeding all variants of Roserade (meaning you can stuff any attempts of your opponent using Sleep Powder or Spikes). The rest of the EVs go in SpD instead of defense since they let Mew tank Super Effective Special attacks a little easier (EX: Choice Specs Zoroark & Sub Lefties Chandelure have a 6.25% chance of OHKOing Mew w/o SR damage, which is fairly respectable since most Mew tends to hover around near max HP due to Softboiled).
I'll test the normal gem lead set, but for now you should hold off on it. It looks promising.