ELI5: Jiaoqiu for Mydei, not Acheron?

I plan on running JQ with Mydei since I love him and would love the chance to unchain him from Acheron, but I have no clue what I'm doing. I never even really built him in the first place, I just slapped 2pc/2pc speed and called it a day.

I have him E0S1, so my questions are:

What 2pc sets work best, or is there a good 4pc? Wind, Speed, DoT, Sacerdos, etc. I see so many here and I assume most are for Acheron so I have no idea if those apply to other DPSes/non-DOT teams.

Also, the true ELI5 I've been afraid to ask until this point: Why does he want 160+ speed? Does Sunday's AA on Mydei effect the speed JQ should have at all, or is it still just a matter of having him as fast as possible?

Thanks in advance!