i would be packing the short/kurz one, as usual

...
Lol
But seriously folks, for a lot of guys here it presents a problem.
1. Tropical climate precludes jackets most of the time.
2. Overweight guys like me don't get along with anything around the waist. I envy skinny guys.
Here is my take on the question...
Gun...something similar to whatever is vogue for L.E. eg. Small sw or glock or sig.
Ammo...again, same idea. 9mm like hpd issue.
Holster should fit your body and normal dress style.
If you are slim and usually wear jeans or slacks, you can do anything.
If you're like me, chubby, you gotta get creative.
One of my all time fav rigs is the Blocker or Galco upside down shoulder rigs. You just have to wear a tshirt then conceal the rig with a photographer vest or even an unbuttoned sport shirt. Those rigs also hold 2 mags or speedloaders under the opposite armpit to balance you out....extremely comfortable.
My other fav carry technique is the fanny pack or man purse. On scorching hot days like yesterday, you can walk around the mall with a tank top and board shorts with your fanny pack and look absolutely normal. The only downside is that you have to be always aware of where the bag is. Understand that I am talking about bags made for that purpose, usually with a hidden compartment for your firearm, and heavier straps to support more weight.