I think it's fair to say that Shades are one of the top DD's in game right now, and I don't think there's any planned/forced usurp of that position with 18.7.
That said, I'm not convinced raw DPS is going to be the main attraction anymore with 18.7.
In 18.6 with a crat+enf+doc+keeper in team, you can just cruise through most encounters, with big badass boss hits only getting through 1 every 30ish seconds or so if the doc spams fling/normal's to light up procs while crat keeps his debuffs up and keeper didn't forget to buff prior to starting content. In this scenario, DPS is the next highest utility. Spam dmg and end the content fast so we can get back to whatever it was we wanted to do.
But post 18.7 I think there's going to be a real need for people to be reconsidering the value of damage mitigation.
Consider:
Enf has 25-30% less HP right off the top.
Total crat debuffs are about 800 inits less than 18.7
Many Doc's may opt for silverback instead of lust/tro setups which may result in reduced proc chances
That means a lot more damage getting through the holes in Ward - and that's IF you can get a keeper.
What that means is that there may be a greater degree of focus on requisite damage mitigation strategies and healing in opposition to raw DPS.
While shade has strong raw DPS, they also have some utility on damage mitigation. The question is, what else will be needed?