As a gun carrier, I find the LCP to be an absolute necessity in any gun collection, for folks that carry 365 days a year. Its not my every day carry firearm, but I do carry one probably once or twice a month while wearing a bathing suit and I'm just running to grab some milk or something. It fits, when nothing else will. It allows you to carry A gun, rather than be unarmed.
There are hundreds of different types of guns, and they all have their use. The LCP fits the bill as a deep concealment pistol, and it does it well. Mine has never jammed once. Ever. Its very reliable. My collection will always have one.
Glock 42 .380- Its a lot bigger than an LCP. It also shoots a lot nicer. Yes, its a better gun. But like I said above, the LCP and the G42 kind of serve different purposes. The G42 is not as good of a deep concealment pistol. I've owned hundreds of pistols, and still own dozens, and THIS G42 pistol is my most carried. Its just flat out a good carry gun. Reliable, fast follow up shots, easy to shoot, reasonable ballistics. I'm a BIG fan of the G42 pistol. I think its a better gun than the larger G43 as well...
If you are trying to find a smaller pistol to carry than a LCR, then the LCP is probably a good choice for you.
One other note, the LCR is rather largish, compared to the similar Smith & Wesson 642/442. I've carried the Smith j-frames for years as well, and found them to be much easier to carry and conceal than the Ruger LCR. The Ruger trigger guard is larger, its rubber grip is much larger, and a lot harder to conceal, than the standard j-frame grip. If you like the revolver format, than check out a Smith 642 or 442 or shrouded hammer 638. I think most people find the Smith easier to conceal than the Ruger.
Heel release is very rare these days. Hard to find, and usually only on obsolete and/or ancient firearms.