Sparks, what has worked for me here is playing some 1/4/5's in the various keys using the basic bluegrass bass/strum. Many times i'm just not warmed up good enough. Put the met on a slow tempo, and just bump it up as you get warmed up. The good thing is you will commit to memory the basic chording in the various keys.
I have a cool worksheet that i got at fretmentor's guitar 1 class, where he mixes up the progressions to include the 2/3/6's, which relay expands your knowledge of playing in the key. Good stuff, i should take my advice and practice it more.