When playing i often find myself spending some time in the family-tree to plan on further actions, to keep my tribe healthy and sometimes to set breeding goals. As i see it, this is what the family-tree is really good for and the filters provide some aid for that. However, i think a couple of improvements can be made, some simpler, some a little more complicated:
life expectancy visible
show the life expectancy, as visible on the map over the portrait of the selected Nicheling, over the full body depiction in the family-tree as well
viewing the selected Nicheling when exiting the family-tree
currently, if i've found what i am looking for over the family-tree, a Nicheling with specific properties, i then have to remember or mark it somehow to find it on the map - so, simply keeping the selection when exiting the family-tree would make this easier and faster
sorting options (different to filters)
so far the "sorting" in the family-tree doesn't make a lot of sense to me. Younger generations are generally put under their parents, but they are often put next to, or even above much older Nichelings, sexes are mixed, even identical twins can be put apart from each other... seems somewhat random to me
the possibility to arrange Nichelings on the family-tree freely, or in self-selected groups could provide more and better information on a glance
this could be possible through simple drag&drop, or through the possibility to divide the family-tree in columns with selected criteria
this could also extend to the order of tab-selecting Nichelings (which currently seems rather random to me as well), making selection easier every turn, as you can influence the order and know what to expect
for tab-selection i also suggest a key for reverse-cycling
easier visibility/ "tracking" genes
when breeding for specific genes, the filter options are ok, but when filtering, you often have to check individuals if they are actually still alive (as the filter overwrites the present/absent status), or if they are otherwise viable/ wanted for breeding. Best example is when trying to breed with healthy immunity, you have to chek for pretty much every immunity gene seperately, which can be a drag.
the possibility to view the actual representation of certain genes as numericals (gene X is present in the population Y times), in the family-tree, or generally on the screen (currently the left middle seems free) could make this a lot easier
this could work like so: you can select the genes in the family-tree to track, which then shows as a numerical for genes present in the current tribe
this could be further customisable when linked to selected groups, columns, or other criteria selectable in the family-tree
Somewhat unrelated to the family-tree i would also add a small suggestion: A key to use as an action for Nichelings to "wait". This would be useful for Nichelings which already are in a spot you might not want to move them away from, but where they also can't use up all their actions (often the case for pregnant females who just got in a nest). So you just order them to "wait", they lose the rest of their actions and you don't have to skip them yourself every time cycling through the tab-selection.
Well, that's what i can think of right now. Sorry the list has gotten rather long, though i would be happy if one or another of these things would be implemented in the future.