Forgot one thing: turning off texture filtering for all maps will reduce color bleed and speed up your renders. I've got a script here in freestuff (Poser 7 texture filtering utility) that can do this for you.

As for deleting unused morphs, it saves memory and cuts down on disk swapping.
V3 and M3 use the injection mechanism to save memory, but many other figures come with all their morphs loaded. This does not depend on Poser version, but on the figure loaded.
There's a RemoveMorphs script on my freestuff page that'll strip all unused morphs from the loaded figure(s), reclaiming quite a few MBs of memory.

The pen is mightier than the sword. But if you literally want to have some impact, use a typewriter

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