Thinking about it some more, it would be fine to simply tweak the profie edit page instead, where I spend the vast majority of my time, these would significantly improve the navigability from that screen to all related profiles. These are all in the 'Edit Family' section of the page.
1. For father, mother, and each spouse add the small icons for tree view and family group view, next to the  link, which shows the tree or group view for that related profile.
2. For each sibling and child add the icons for descendant list and family group view next to the  link, again for that specific profile. Similar to what we have in the family group view.
2A If not too calculation intensive, only show the icons if they are applicable, i.e. don't show a family tree icon if no parents are attached, don't show descendants or family group if no spouse and children are attached. This could be a later enhancement.
3. Add the pending merges and umnerged matches list somewhere on the page, i.e. below the list of children. I don't really need to see the rejected matches. Sort them in order with the lowest numbered ones first.
4. If two spouses or siblings or children have the same name and are not rejected matches, a compare shortcut for the two to make merging easier. Just show it next to the higher numbered profile with the lowest numbered profile as the target profile.
I think these would be more easily navigable than a second navigation bar which would appliy only to the specific profile I am working on. It would also be easier to pick out the icon you need if there are only two together, rather than the 12 that are next to each other on the profile view page.