I've previously played around with various iterations of multipart minis. Multi-part works so well for traditional mins, because all the small pieces are attached to a single sprue right up until you clip them off and glue them together. But the issue is, with 3D printing, all those small parts are usually on individual supports, and there are various stages where they can get lost - during the print, during washing, during drying, during curing etc. Additionally, rather than the instant and almost magical satisfaction of just pulling a mono-posed miniature off the supports, you have to pull a dozen pieces off, which then have to be assembled, so it's a time and frustration thing. Personally, the balance I like for multi-part 3D miniatures is modular heads with a ball and socket joint, so you can customise the visual look and personality of each miniature - a different head, or even just having a head look the other way can tell a completely different story to the miniature. I also usually separate shields if the character has one, again for easy personalisation, and so both supports and a paintbrush can get to the areas that would be obstructed by a shield. Sometimes, you might want a weapon swap - but something with the arm or at least the hand included is best, and sometimes it might just be a practical reason - have the forearm with the spear as a separate part for ease of packing and shipping, or so prints don't take as long. There's by no means a hard and fast rule though - there's definitely different balances to be had. Different situations will call for different approaches, and there's a balance between restricting your sculpt, and restricting the customisation and conversion potential of a miniature.