If I'm playing in C, for example, I'd play a Cmaj7, followed by a full diminished B. (Diatonically, in the key of C, B is normally a half diminished [1 b3 b5 b7], I use the full diminished to add some colour. [1 b3 b5 bb7])The B may sound a little off, so I bring it down to the next chord in the key, the vi, Am7.
Another way to emphasize a chord change is by adding some chomatic root walkdowns/ups. down if you're going lower, up if you're going higher.
Bm7 -> E7, I'd hit an Eb just before the E7, and it has a walking bassline feel.
Of course, if you're playing in a band, you might save that for the bassist.
