Now during creation of the character such sub races of skeletons as are available:
Basic race - Skeleton
Sub-race - P4 Unit and Screamer MkI
It would be desirable that added also - Soldierbot, Skeleton P4MkII, Skeleton Log-Head MKII.

I will be very grateful if they appear in the nearest future.

Soldierbot 57782-Newwworld.mod
Skeleton P4MkII 65266-Newwworld.mod
Skeleton Log-Head MKII 66529-Newwworld.mod

Yes it is possible to add all sub classes as long as they have a particular file. Any recruits I add which take you to the edit screen upon recruit will also be available as a starting race. Of they don't have that file (it's the vanilla edit file) then when they recruit they'll just join without edit and won't be available at new game. Skellies should all be ok.