I second this approach; draw + shoot, mag reload, jams, multiple targets, movement drills...there are tons of drills out there that can make you better while saving ammo. I usually use 100 - 150 rounds per training session but I could definitely use less if I had to and still get quality work done.
Each their own but most national training programs have gotten away from a bunch of magazine changes. They do it a couple times or maybe in a course of fire but the mail. Reason it just doesn’t happen in CCW incidents (and most LE either) sure you can find a few or cherry pick but usually when that happens it’s because the LEO mag dumped without hitting anything (or not putting rounds where they stop someone) and the whole point of defensive shooting is to stop the dude.
Not saying don’t practice a mag change just don’t get fixated on them as you do so many just administratively in the unlikely event you have to make a change (only been documented like once) you will be fine
And with ammo prices almost double pre pandemic that makes sense.
And to park phrase what Tom Givens preaches everytime you go to the range every bullet fired should have a purpose