I've reconsidered and may now add Habitat List as a function of Prof. Oak's PC. So you'd get a choice of Habitats, Rating, or Log Out. Habitats would list locations, and selecting one would list the species, along with caught indicators and maybe time/method indicators.
I didn't use the Habitat List in B2/W2 myself, and am not personally interested in completing the Pokédex, so I'd like to hear more from someone who does and says the Habitat List was their "absolute favorite feature". (DexNav was apparently popular too.) What was good about it, the info specifically, or something about the graphical presentation? Does the Oak's PC thing sound OK?
The Habitat List was the feature that got me to complete the Unova Pokedex on B2. I'm a completionist at heart, so having an indicator of when I've "finished" an area is a big deal to me. B2 had several Pokemon that could only be found rarely from phenomena (the grass shaking that normally spawned an Audino), a few Pokemon that were rare in normal grass, and a few in the dark double grass. Knowing that there was still Pokemon for me to find on the route kept me there longer searching for them, as it was a lot of fun for me to make sure that I wouldn't have to backtrack later. If you didn't know that the Ruins of Alph was the only place you could get a Smeargle, for example, you might run around and encounter 4 or 5 Natu and decide that there's nothing else there. The Habitat List being readily available on the route itself is a big deal for this feature (at least for me), so the Oak's PC implementation would probably make it so that I'd never use it.
Aesthetically, the Habitat List was nice as well. When you saw all the Pokemon in an area, you'd get a gray Poke Ball stamp on the list and it made it feel good to fill it up. When you caught everything on a Route, you'd get a colored stamp. It sounds dumb, but it just felt good to fill up the list. They did a good job making it feel rewarding with those little touches. Even if you haven't opened the list in a while, the stamp animation would play the next time you opened a completed route that hadn't been stamped yet.
Obviously, you don't need to full on emulate this for the list to have that effect. But I'd be wary of making the list inconvenient to use by requiring tons of scrolling. Not being able to see all the entries at once makes it more difficult to know at a glance what you're missing from an area, and not having it on hand while on the route in question would compound that issue. In B2W2, you could assign the list to your quick menu as well, so you could quickly pull up the list in 2 button presses, check what you're missing, and be back in the OW in less than 5 seconds.
The Habitat List also clearly delineated whether the Pokemon came from the grass, surfing, or fishing; but if space is at a premium for the list hypothetically getting a GUI, the delineations should probably be done by time of day.
I did not find the DexNav to be as good as the Habitat List. Being able to draw specific Pokemon to you undercut the need for the list and the difficulty of encountering rare Pokemon in the first place, Hoenn changed its wild Pokemon pool after encountering the Primals (so you had to backtrack anyway), and aesthetically it didn't look as nice (with the Pokemon scattered around haphazardly). There was also no nice visual indicator (as far as I can remember) congratulating you for completing a route, which made catching everything seem less rewarding and important. I also had a complete Living Pokedex when ORAS came out, so I may be biased a bit by not needing to catch any Pokemon for those games.
EDIT: Also, card design #2, but the Money looks a bit cramped at the max value.