I went through this a couple years ago when I was shopping for my first pistol. Through friends I was able to try a couple 1911's in .45, a .357 revolver and a couple Glock variants in 9mm. Of all the handguns I tried, I actually liked the ergonomics and shooting consistency of the revolver the most, but for various practicality reasons, reloading being primary among them, I decided against getting one for self-defense. I liked the ergonomics of the 1911 the least, although being such heavy guns, even in .45 ACP I didn't notice recoil being much worse than the Glock 9 mm, and they're pretty easy to shoot accurately.

I ultimately settled on the 9 mm and got what many consider to be a Glock knock-off, the S&W SD9, but it's known for being one of the least expensive guns out there, it's super reliable (most reliable semi-auto I've ever fired), and accurate (for a handgun) if you can get over the heavy trigger pull. Some range time and I was able to quickly work around that heavy trigger.

I also liked the price and availability of the 9 mm cartridge, along with its proven track record in police, military and self-defense use. I also like the fact that many rifles have been coming out recently chambered in 9 mm, which would make it a good candidate for inexpensive and low-recoil target shooting at the rifle range without needing to carry multiple calibers of ammunition.