On the subject of Regiment Creation rules, several planet types, Notably Forge world, are missing.
Could be added:
Armory World + bonus to Logistics roll, 15% Chance each item, Item in kit is good quality.
Forge World + Bonus to Logistics roll, 1 kit item of Good Quality (Higher bonus to Logistics roll than Armory world.)
Agri World + Bonus to Logistics rolls for non weapon/ammunition rolls
Pleasure World. +1 Insanity, Many bonus to Social skills
Regiment type could use two addons as I see it
Conscript Infantry
Penal Regiment.
Penal regiment is already mentioned in the Planet section. This would further differentiate them from other infantry units. After all the Penal Regiments are used as cannon fodder. Penal Legions should benefit from a higher XP bonus as they are ONLY used in no win situations. The higher XP bonus denotes the level of stress the Penal regiment is under.
Concript Infantry should receive a major negative bonus to logistics but have the ability to be "promoted" to one of 3 types of regiments later on (Mechanised Infantry, Line Infantry or Light Infantry.) To do this the Character would loose the negative bonus assigned by the "Conscript Infantry Regiment" and gain any Positive training bonus from the replacement regiment. EG the 501st Conscript regiment after 5 missions, was promoted to the 501st Mechanised Infantry regiment after receiving their "Ordo Imperalis" Medal promoting them from Conscript to Full infantry status.
Also I see issue with the fact that some combinations get you Aptitudes and others do not. That means more often than not if the PCs are going to create the regiment then they will choose the Aptitudes (to lower costs of skills, Talents and Characteristics.) I suggest that either ALL or NONE get Aptitudes, OR, Make Regiment creation part of the GM rules and not part of the player rules.
I my group I created my own regiment, as best I could and I am getting constant complaints by my players that things cost too much XP because my regiment build does not grant any Aptitudes.
Just some thoughts to share.