• When created (by being trained by our mercs), they start with basic, randomised stats. We can rename this process 'recruitment' or 'basic training', it works like the current militia training.
• In combat, they can gain stats and experience just like our mercs. I still think a faster rate would be reasonable here - they don't get near the combat experience our mercs get.
• In some sectors, they will train just by being there. Examples would be the Alma shooting range for MRK or the Cambria hospital for MED. No need to assign anything - any militia there will train those stats somewhat, so we do not require any assignments or orders.
• After 'basic training', our mercs can still train militia, but a bit different this time. This process is now renamed 'advanced training'. It does not cost money anymore, but also does not create new people. For each trainable stat a trainer merc has, we calculate a pool of learning points. These are then distributed among trainable militia present.
  A militia can only be trained in a stat if the trainer has better stats. Similar, a militia will only gain experience if trained by someone with more experience.
  The amount of points a trainer generates in a stat depends on his own stats, his leadership (leadership somewhat represents how good they are at teaching others), their personality, teaching trait etc.. As a result, the trainers need to be good at what they are teaching, but also need to be at least somewhat good and leading.
  I don't see the need to have a separate training assignment for each stat - just have one assignment for all of them. The stat makeup of the trainer determines where this training will work best.

As a result, it is no longer viable to park some crappy mercs in the hinterland an have them train veteran platoons all on their own. It always seemed a bit wrong to me that Biff, Flo and Ira could train hordes of battle-hardened troops.
With this new system, low-level trainers would still perform the basic training of militia. Advanced training has to come from mercs who have an idea of what they are doing. In the ideal case, you would combine this - if you want your militia to be better shooters, the best place to let them be trained in the Alma shooting range by the likes of Len or Scope. If you want medics, let them learn their skills from Spider and Cliff in Cambria - they might not learn EXP there, but their MED should go up.