Reticle implants, drone infra things, thermal scopes, psionics, helmet/armor add-ons, each make an option avaible. If you have psionic with you on a mission, next to the Map button theres one "LoS" and one saying "Normal" you have to click on normal, and choose which you want, but it only shows which is avaible for at least one of your squad members.
Hm i odnt like to hire high level soldiers from other factions, they are not advancing the way i want... I usually hire lvl1-5 guys, and use the ones i got at the starting. Betty died from the starting four, but David, Neil, and Sue ar the lvl 20-21s now
Evil? What can be more glorious aim than cleaning mankind from the dirt? (think about warhammer 40k a bit first i wanted to do the same, but then aftershock's difficulty came to my mind, and i dropped the idea ^.^ And even space marines have librarians, tech priests, and psionics...