Training facilities automation ideas.
I don't really mind the idea of setting up a training base. It works well, and is not too difficult. The semi-regular maintenance of the training roster is not a massive chore either. About once a month, I rebalance the training assignments, bringing up gals who have less than others. The trait I use as a lazy Guiderule is TUs, as I want everyone to have 100 eventually.
Train the Rookies. - The routine would find the least experienced soldiers and focus on leveling them up. Maybe the routine runs at end of month with the other maintenance there (or maybe at every Geoscape auto save which is every ten days for me). At "evaluation time" it would check soldier training again, maybe using a total of all training points and start from the bottom and fill up the training roster again. Maybe this should be the default option.
Train a Cadre. - In this instance, you would want to train a group of gals up to the highest level. I'm not sure on how to single say, 20 gals out of 40 for this treatment. Maybe train cadre opens another UI that allows you to "select" which gals are part of the cadre, similar to the one used to assign them to a vessel, or even the armor assignment list. Otherwise this would be similar to train the rookies. If you had 20 gals assign to the cadre but only 10 training space, it would level out the progress by ensuring that the least trained ones would always be catching up to their peers. A simple approach would be to only select enough cadre for your current training capacity.
Sick Leave. The routine would identify a wounded soldier and check to see if they were in training. If so, it would assign them to "sick leave" ( add a marker in the save game) and then select a different soldier from the pool according to the setting (rookie/cadre/etc) and assign them to training. Once the convalescence period is over, at the next evaluation period it would release the substitute student and put the recovered soldier back in.
I suppose that with Smart Training facilities like this (Maybe they are an upgrade?) you could forgo the "Training Base" and just include a facility or two in your operational bases, but that may vary with play style.