Lets compare Shades to traps and stealth.
Traps are invisible, can be stacked in control point and stay there for a long time. If traited/geared properly they are deadly. Trapper DH with bow is most powerful trap user.
Stealth gives invisibility. Can sneak up and unleash a burst of instane dmg before we can react. It work as defensive mechanism as well.
Shades, unlike traps or stealth are visible and not active before scourge activate it, paying with LF. Even full burst of F2 to F5 wont kill in any scenario. They telegraph their attacks clearly and can be countered with condi cleanse. Whats more, shades are far from being defensive or bursty. Now with reduced condi cleanse they don't support as well. Shades last only 10 seconds.
Traps - invisible, long-lasting, deadly, almost no way to avoid
Stealth - invisible, deadly, defensive, no way to reveal enemy (there are few skills accessible by only couple of classes)
Shades - visible, short lifespan, weak, delayed and telegraphed activation.
Reduce duration of traps to 10sec. Make them visible. Put a 0.5s delay after stepping in to avoid.
Stealth - give access to reveal skill to all classes, spread between weapon skills, mechanics and utilities, daze stealth-users when exiting stealth for 0.5s, Make a graphical information when player leave stealth (big red circles going inward player locaton).
All AoE skills need to be put on minimum 0.5s delay with visible activation location (lava fonts, glyph of storms, arrows barrage etc). They are more powerful than unavioided shade anyway.