We do have Spacekru page.

For Hesperides, we do have a page for each pair combo, so having a fourth page for the three would be overkill.

For HEG, we can justify separate relationship pages between each of the pairs - all three are main characters with continued interactions in further episodes. Since those pages can be created, it's the same as Hesperides, with a fourth page being overkill.

For HEG(O), Orlando was too short lived of a character (onscreen) to justify separate relationship page with him. At this time, I think Orlando's own page is sufficient.

Can I at least link to Spacekru on the family relationships category page? I just feel like having only two-people-relationships on there doesn't do the show's multitute of "families" justice yk?

At this time, no, sorry.

I'm currently trying to decrease the categorization disarray, so starting to categorize group pages within relationship categories would be the opposite of constructive.

As for the navboxes, Spacekru is already within groups navbox, so there is no need to add to relationship navbox. Obviously groups are a form of relationships, but the relationship navbox is currenly limited to pair relationship pages.

I don't want to start this right now, but in a couple months if you want to come back to this, we can have further discussion of creating family pages. (The examples you listed above, as well as more traditional ones like Blake family or Griffin family.)