when i was playing spectre i never take desolate on early game, and i prefer more tanky build on spec because i love to rush in when the clash happen.
my skill build on spectre is Q,E,Q,E,Q,R,Q,E,E,W,R,W,W,W,stats point,R.
for my item build it's not much differ from clenz and phoenix.
-phase boots(core items)
-midas(situational)
-yasha(core items)
-blade mail(core items)
-bkb (situational)
-manta/sangyash(situational)
-diffu(situational)
-HoT(core items)
-Radiance/butterfly (depends on situation)
radiance/butterfly is a must, because this item is my main damage source of this build
for midas you can go by this if you rarely being targeted and got free farm all the way, its obviously can provide some decent gold and exp too