The gen 4 is smaller, and with a little effort I find it's not much of a problem with my stubby fingers. It doesn't fit one handed like a 1911, but after adjusting to the g20, i find the larger grip gives my weak hand more surface area, which helps to get a proper 2 handed grip. I have to reposition less with the glock even though the 10mm has more recoil. I have an m&p 40 vtac, which felt like the perfect gun when I started shooting. I've now come to appreciate the glock grip. As a noob, I shot the m@p better. With 10k rounds under my belt, and an understanding of pistol dynamics, ... Both are about the same out to 25 yards lol. I do shoot the glock better out to 100 yards though.
The other option for smaller hands is a 1911 in 10mm. You might lose reliability, easy caliber changes, and easy customization, but it's hard to beat a 1911 for simply feeling nice.