Max wound allocation (in a minimum sized unit) for Wraiths is
Wraith - Standard
Wraith - Particle Caster
Wraith - Whip Coils
Wraith - Trans dimensional Beamer
The way you have it now, you only get to mess with 2 wounds (1 on a whip, 1 on a pistol) before you start killing off models. The way I have it set up above, each get to soak a wound before someone must die (Instant Death not being accounted for which kills full models).