Thanks for the feedback so far.
While the screen was on Beta, there were several suggestions as to how it could be improved. A lot of Beta testers wanted a better way to view defensive units, which we have since implemented by moving all defensive units to the front of the unit pool. You can see it in operation next week
Another thing we added after listening to feedback, as you've noticed, is the age filter. Overall, the screen is a big improvement on the old one, and - while there is no unattached units filter in the new screen - this was not part of the old screen, so it hasn't gone "backwards" in any way and the new screen is still a major improvement.
Having said that, something to show unattached units was fairly high on the wish list from Beta, and I can tell you that there are plans to implement something to address this in the future. However, because of the need to prioritize, we are unable to always implement requests before releasing a feature. But it is on the cards.