I don't have a list but I liked Josh Rouse's album this year. Liked the Mountain Goats pro wrestling themed album. I like Work Part 1 from Walter Salas-Humara doing new acoustic versions of his old Silos songs. And I really like an album from the Tripwires called Get Young but it came out in 2014.
These LPs are not necessarily unknown, or a secret to most, but right now I am hooked on Chris Stapleton and Leon Bridges. Two completely different genres but excellent albums.