I'm actually kind of enjoying the partitioned nature of the fed. I use the Jerboa app when on mobile to access Lemmy, and when I'm on my PC I use kbin.
When I was on reddit, I'd switch from mobile to PC or vice versa and just see all the content I just browsed on my other device. Now it's a fresh batch every time I make the switch (which is pretty regularly!).
That said, I wouldn't be opposed to a unifier. I remember back when AOL Instant Messenger and the 5 or so similar IM services were the cream of the internet, and keeping up with friends on each was a real pain in the ass. Then a program called "Trillian" came along and linked them all together with one clean interface, and it was fucking amazing. I could definitely see the fed benefiting from a similar service.
Trillian was good stuff. Then came Pidgin, which was free and open source if I recall correctly. At one point I had AIM, MSN, Yahoo, Gtalk, and ICQ all going at once.