I just tested them to be sure:
No they don't. Same damage in any point of the eclipse bar.They scale with nature eclipse as they deal nature damage.
They do but it's dynamic-delayed, so they need 2-3 sec to register newly gained or dropped haste effects if they didn't happen before they were summoned.They scale with the haste you have when you summon them
Dynamically again.They scale with the spell power you have when you summon them
They dont seems, or maybe its a bug, to scale with the crit% you have when you summon them.
Dynamically again so when your UVLS buff dropped their crit dropped too.I tested them on a dummy, I have the trinket from Megera and the crit one from Lei-Shen, When my lei shen trinket proc I used all 3 charges, and for the first 7-8 seconds, they always dealt a critical strike. After that, the 100% chance to crit faded. Im not sure if its a bug or something, but just because of this I feel like Incarnation is better. ;(
I do love them in PvP and Brawler's arena though :PIt just seems to hard to use in pve, you would need to keep one charge on CD all the time to not waste them and only use during trinket procs.
I enjoy in pvp against certain comps.