I suppose since you live in CA, you can?t carry a handgun on your person? So your primary use will eventually be just competition and home defense?
If you carry, was gonna recommend definitely practicing live fire exercises drawing from holster, engaging at least one target (2-3 better) from varying distances (7yds, 12yds, 20yds, max 25yds), then safely reholstering.
You don?t have to ?rapid fire? as in see how fast you can dump a mag, but a simple timed drill with two to the chest and one to the head is a good drill to help you reacquire your front sight onto your target quicker and improve accuracy under simulated stressful conditions (the shot timer going off)
Have a buddy mix in some dummy rounds in your mags, so that you can simulate malfunctions and go through steps to clear them and re-engage target. That will also help simulate stressful conditions and help you speed up your clearing malfunctions process to get back in the fight quicker.
Practice shooting from non-standard positions...leaning around barricade (Left and Right) and over barricade, sitting, kneeling, laying on your belly/back/side
Practice shooting one-handed with your weak hand (simulates if you got wounded in your strong arm/hand) a lot harder to do accurately than one might think I you don?t practice.
Do some drills that require you to do mag changes (regular empty mag changes where you just drop empty mag to ground, and reload and ?tactical reloads? where say you know or maybe aren?t sure if you?ve only got a couple rounds left but have multiple targets to engage. Behind cover you drop your mag but retain it cause it still has rounds left, but you go ahead and reload a full mag.
You could practice shooting on the move and moving from point of cover to point of cover.
Almost all public indoor ranges are going to be a lot stricter on doing these kinds of drills, even many outdoor ranges are unless they have a designated ?tac bay? but maybe if you go early before it gets busy or late, and talk to them about some drills you?d like to do, they just might let you. I have a couple that are that way but just cause they?ve gotten to know me and know my background in the military and know I shoot IDPA matches regularly, but the big thing is they watched me at first so knew I could do these things safely and proficiently. If IDPA is in CA, highly suggest you join them for a match. It?s a helluva lotta fun, and you are able to practice lots of different and more realistic shooting scenarios. Even ranges that don?t normally allow drawing from holster, waive that when IDPA matches are happening. It?s not just ALL about competition either, there are shooters at all skill levels, many who would be like you and just want to hone their skills in a realistic training environment.
If all else fails and you can only stand at a lane on the range, use smaller targets to shoot at...like those small 6? targets or even 3x5 index cards (aim small/miss small) to challenge yourself. You can still incorporate some aspects of the above drills but without getting kicked off the range.
Can think of lots of other things we?ve done in the military but the things I mentioned are a good start.
Good luck man! I commend you on recognizing the need to up your game and striving to become a better shooter. Too many are satisfied just standing in place and punching holes in paper and done. That?s fine and can be fun too, but if you plan on using your guns as defensive weapons you really gotta do more if you are really serious about being successful at it if god-forbid you had to do it for real.