In Warband, if you are not willing to invest all your levels points in Intelligence in order to get the Training skill as high as possible, consider to focus one of your companion on getting this.
It makes a huge difference in how quickly your recruit will be trained into better troops.
At very high Training skill (you or one of your companion), it's not rare to get all your recruits leveling up to their next status after the 1st day of their recruitment by example, while at low Training skill it can take days and only for few of your recruits.
If you play with Campaign AI at more than "Poor", this skill is simply vital for your kingdom survival because Campaign AI set the quality of the lords troops.
At poor it may be a mix of troops of different levels several simple footmen and archers, a few marksmen a few knights etc ... , allowing you then to take your time with your troop leveling (so not necessary to have a high Training value) and getting in fight with them with not so high-end troopers.
But at Campaign AI set to the maximum, you'll face legions of knights/mameluks and ranged very precise marksmen/sharpshooters that will tear your army in seconds if they're not high end soldiers themselves.
You really want then a very high Training skill to avoid getting very disadvantaged when going at war with an enemy kingdom in Campaign AI at more than "Poor"