when i started playing, i was using a 12.75 hardball glove, didn't know any different, and it seemed to work fine. I played mostly outfield at the time, and i eventually looked into buying a softball specific glove. I ended up with a 14" and i also started playing some SS. so i decided i would use the 14" in the outfield and the smaller one in the infield. once i broke in the big glove though, it really had no downside. there was no reason for me to not use it in the infield, and 5 or so years later, wearing the 12.75 feels like playing bare-handed. maybe a 12.75 hardball glove is smaller than a softball version, but mine can't even close around a softball and i always wore it with two fingers in the pinky slot to make the pocket bigger.
i understand it's all going to be preference, but as long as it's a decent glove that isn't super floppy, i just don't think there's any downside to having a couple extra inches. the way i see it, there's been dozens of plays where i would have missed the ball with a smaller glove, and the 'get's lost in the pocket' thing only happens if you can't reach the ball. so, literally every time the ball has been lost in the pocket, i would have straight up missed it(well likely tipped it and knocked it away) with a smaller glove. when the ball is hit near me, i simply play it like i have a small glove, catch it near the palm, and it's just as easy and quick to release.
so for me, there's zero downside to a larger glove. i haven't tried anything bigger than 14" and i'm sure there's a point where it's too much, but i feel anything under 13.5" doesn't really belong on a softball field and only works because the user has adjusted to it, or refuses to adjust to a bigger one. which is ok, you do you, but don't confuse "training yourself to use a small glove" with "small gloves are better". i'd say it takes a lot more skill to use a small glove effectively, which is why i'd recommend the larger one