Here they are, since 2000, broken out by year and position. There are the "playmaker" stats +WPA and +EPA, but there's also Tackle Factor (TF). There are conventional stats too, including interesting stuff like passes defended, tackles for a loss, and QB hits.
For now linebackers are all lumped together, without regard to 3-4 or 4-3 scheme. For that matter, tackles and ends are lumped together as well. In the future I'd like to differentiate positions by scheme.
I also plan to add some more stats. For example, "victories" (or some other lame name) would be the number of plays that a defender made that resulted in a loss of expected points (EP) for the offense. They could be stuffs, passes defended, turnovers, sacks, or even tackles 6-yards deep on 3rd and 7. I've left success rate (SR) in the tables, but for defenders I think the total number of successes makes more sense.
The tables are sortable, with the default sort key set to +WPA. I think +WPA may be the most interesting stat, but +EPA is going to be a better indicator of long-term player ability.