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Among .22 pistols I have or have shot...
Ruger Mark II 5.5" Bull Barrel Target -- Eats nearly anything and very good/excellent accuracy. Terrible to field strip and reassemble, but EABCO markets a handy take-down mechanism that I may check into. Grip angle very different from 1911. Heel-type magazine release.
Ruger Mark III 22/45 5.5" Bull Barrel Target -- Eats nearly anything and very good/excellent accuracy. Terrible to field strip and reassemble, but EABCO markets a handy take-down mechanism that I may check into. Grip angle / control placement similar to 1911, but magazine insertion is not straight in-line with the grip angle. Some issues feeding/extracting that may be related to the loaded chamber indicator.
Beretta Neos 6" - Eats nearly anything and very good/excellent accuracy. Trigger out of box was unsatisfactory, but a trigger job later and it is a good shooter. Relatively easy take-down. Grip angle very different from 1911, as are controls. Large/wide hands will find the safety uncomfortable when on safe.
SIG 1911-22 -- 1911 styled single action semi-auto. Eats nearly anything and good/very good accuracy. Take-down requires a hex wrench. No Speed-bump on grip safety, so some folks have difficulty with the gun due to the curved mainspring housing.
Kimber .22 conversion on Kimber 1911 frame -- feeds/runs CCI Mini-Mags fairly reliably - any other ammo is questionable. Good/very good accuracy.
Walther P-22 -- Not finicky about ammo. Good/very good accuracy. Early examples prone to several issues.
Ruger SR-22 -- More finicky about ammo than the Mark series. Good/very good accuracy.
S&W 22A 6" -- Not finicky about ammo. Very good/excellent accuracy. Easy take-down. Grip angle similar to 1911, but grip overly large and not a good fit for me/my wife and the new shooters we work with. Magazine release is on the grip front-strap. Also, slide manipulation is more difficult than similar guns like the Neos (due to how the surfaces are milled for gripping the slide).
S&W M&P 22 (full size) -- Replica of the full size M&P pistol without interchangeable backstraps. Not finicky about ammo. Good/very good accuracy. Easy take-down.

Ruger Single Six - Single Action Revolver generally styled similar to a Colt 1873. Eats nearly anything and very good/excellent accuracy.
Chiappa 1873-22 - Single Action Revolver generally styled similar to a Colt 1873. Haven't shot it yet.
Heritage 22 - Single Action Revolver generally styled similar to a Colt 1873. Eats nearly anything and good/very good accuracy.

YMMV, of course, with any given one of the guns mentioned above since each company has released both good and not-so-good examples of each of these models.

On my rimfire handgun want list are the S&W Model 41, S&W Model 17, a few of the High Standard models, the H&R Sportsman 999, the Thompson/Center Contender and the Dan Wesson .22 pistol pac. I hear good things about the S&W Victory, but have not shot one yet.

SIG makes a 1911-22 (a re-badged GSG), which is a decent gun. Takedown is a bit different than a regular 1911. I also saw that SIG is selling a 1911 .22 conversion on their website. SIG also makes a version of the 938 in .22LR. Beyond SIG there are others, of course, but I only have experience with their 1911-22 in 1911 format guns.

As for why the limit on mag capacity, the rimmed cartridge is the big driver. The rim can cause problems feeding from a straight box magazine that is too long, and double-stacking rimmed cartridges in a magazine is a recipe for magazine related failures when the rims don't all behave just so during loading or shooting.