I recommend you pick up a Wolff rebound spring pack, contains several springs of differing weight, all below the stock (18 lb, IIRC) spring. The 13 lb spring usually works well, with a reduced trigger pull and positive trigger reset. Try several different spring weights to determine which is best for you.

Also, the Wolff ribbed main (hammer) springs offer help in this area. Usually, the standard weight Wolff ribbed spring results in a smoother trigger pull, with a perception of some reduced weight, and the reduced power version can make an almost dramatic difference. Reliability with the reduced power spring is usually good, may vary from gun to gun, and with different primers, although I never had a problem with either CCI or Winchester primers.

Midway and Brownell's usually have them in stock, and the prices are low enough that you can try several variations and/or combinations without breaking the bank. The springs for K and L frames (the 19 and 586, respectively) are, I believe, the same, so you will be covered by one set of rebound springs (unless you settle on the same spring for both guns), and the main spring you choose for each gun. Hope this helps.

One other thing - both Midway and Brownell's sell a stone that fits the rebound slide track (I believe it is actually listed as a specialty stone for 1911 trigger tracks in 1911 frames). It may help to lightly stone the rebound slide track in the frame, and the rebound slide itself (remember - lightly stoned, a little goes a long way) to smooth out its operation.