There's also another factor in favor of the Type II that's rarely brought up in the literature, for the simple reason that most publicized materials focus on humanoid-crewed ships:

The 'dustbuster' form factor is a lot friendlier to nonhumanoid manipulation apparatus. I mean, sure, it's still not great for, say, a Sulamid, but it's a lot better than a Mk IV. Have you ever watched a Sulamid try to manage a pistol grip with its tentacles? I'd think long and hard about coming in line of sight of one armed with a Mk IV hard-locked to setting 1, let alone any of the higher ones.

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Iä! Iä! Moe fthagn!