To the OP:
I'm going to take serious flak for this, but here goes. (For the record, I've been shooting handguns for more than 50 years, and I've been an instructor (of both newbie civilians and commissioned professionals) for more than 30.)
Given that your first purchase was a 9mm autoloader in a concealed carry format, my recommendation for your second purchase would be a good .22 auto (I happen to like the Ruger SR-22) and as much .22 ammo as you can find.
1) Proficiency with a handgun requires a number of skill sets, including but not limited to simple marksmanship. A good instructor is very useful in guiding you (my view is that you don't so much "teach" as it is you help someone to "learn"), but ultimately acquiring and perfecting the skills is a function of practice.
2) As a rule, .22s tend to build skills, while center fire pistols tend to diminish them (by stimulating bad habits).
3) My experience over the years is that most folks who start with big bores develop a minimal skill set and then never get any higher. There are exceptions, of course, but not many. Counting on being an exception is not a percentage play.
Good luck. Now I'm heading for the bunker!