I have no problem at all using a Ruger 10/22 for home defense. I see no need for the larger capacity mags. I have found the ones that are 20 and less tend ot function more reliabily. I agree that those little rifles point very nicely!
More bullets, sure. But consider what you are going to tell the judge or jury when they ask you why you fired 25 rounds into the perp? Maybe a couple 9mm or 40 S&W would have worked just as well and seemed more "normal" in a self defensive situation.
I generally hold to the opinion that there are better calibers to choose for home defense. That is not to say that a 22 rifle won't do the job. I sometimes carry my Ruger LCR-22 for self defense. I always qualify my "advice" with using or choosing a 22.