Effects of Different Fits

I am curious as to other locked individuals experience with the effects of changing devices on comfort and practicality of constant wear.

Currently, I am in a non-custom stainless steel device that is quite comfortable (now reaching the point that I forget I'm wearing it at times). The ring might be a tad too loose, the cage might be too long, but it is comfortable and works.

Current fit:
As it stands, I have perhaps an 1 - 1.5" of space between the end of my penis and the end of the cage when 'shriveled' or 'extra flaccid'. This decreases to perhaps .5-1.0" when 'normal'. When an erection is strong, I fill the cage and then it pulls away from my body as normal.

My girth can be problematic for insertion, even totally flaccid I tend to bunch up against the metal bars, and it takes routine adjustment to move the skin down the shaft to the proper relaxed state, and after a few days I start getting slightly patchy dry skin. In short, it is more snug in width than it is in length. Arousal results in the flesh of the penis bulging through the bars.

My base ring is probably a little too loose. It falls away from my body with relative ease, but it is comfortable, and I have a setup that holds it against my body for daytime and night-time wear, so this is not a problem.

What I'm looking for input on:
My wife and I have already decided to experiment with different fittings. I'm here to hopefully cull some tips on the effects of different constraints on comfort - and primarily, effect of arousal within the cage.

I assume that a shorter cage (say, one that is exactly as long as I am totally flaccid) will only cause the cage to pull away from my body sooner during arousal (as there is less room to grow). Will a shorter cage instead improve erection inhibition? If it is the former (only pulling the cage away sooner) then I don't see a benefit to shortening the cage from a mechanical standpoint (although, feeling a snug fit is quite nice).

A slightly thinner cage: My assumption with a slightly thinner cage is that I could benefit from it - it could inhibit erections better (keeping blood from more easily flowing into the main shaft) and it would more snugly grasp the skin, causing less shifting between skin and cage, and presumably keeping the skin in place (preventing bunching).

A smaller ring: This is the real question - my ring now is comfortable. However, it does tend to fall away from my body. I assume a smaller ring will help with this. Will a smaller ring help inhibit erections? Is there a "ideal size" that inhibits erections or is that a unicorn? Is there an ideal ring size that won't pull away from the body readily?

And then overall - my device seems to be working quite well. Is it wise to chase a 'better' or 'optimal' fit? Or, does this usually just end up being a waste, and the optimal fit doesn't really exist?

Optimal, I suppose, is a cage that has very few irritant side effects, inhibits most or all erections, but has no discomfort during daily wear, and minimal discomfort at night. Does such a thing exist in reality?

many thanks ahead of time.

Oh, and before anyone asks, visual aids for fitting won't be posted.