I have always seen potential in them as a tag team. Aside from briefly feuding with the Hart Dynasty, they haven't really had any chance to do anything to get themselves over. Unlike the old days when there were a large number of proper tag teams to feud with, moving from the only tag team with a collective gimmick to the rest of the thrown-together teams doesn't really put a lot of focus on the matches or the teams themselves. Slater and Gabriel were thrown together to restore relevance to Nexus and further the Cena storyline, and worked well enough to stick together for the same role in the Corre. They are established enough at this point that they can be used in a proper tag team feud. They could be the perfect stepping stone for the Usos before having them go for the tag titles and make people give a shit about it.
In recent weeks, the Usos are firing on all cylinders, pulling off some awesome tag team spots, as well as individual moves, showcasing their skills in the ring while they have been given new music and the ability to showcase their heritage, which makes them unique from the rest of the roster. Out of nowhere, it seems like WWE are determined to get them over and use them to the fullest extent. I think that that's great, not just for them, but for the audience, who have been getting really into their matches. Is it a sign that WWE suddenly is deciding to give a shit about the tag division? Probably not, as there really isn't anywhere for them to go after winning the titles and the rematch. I am definitely looking forward to at least that much, however.
As an aside, one great thing about the Usos in terms of the tag division is that the chances of them being split are relatively slim. They look too similar for people to make the distinction between them in a one-on-one match, which wouldn't make the angle successful. Unlike basically every tag team we have seen in the past two years, I see zero chance of that happening.