I use alternate chord voicings frequently. Adding, subtracting notes even without changing the chord, to 'imply' movement. The most common ones I use are an addition D in the Gmaj chord; 332033 and an additional G for the Cmaj chord; 332013 (double up on the low G and C with your third finger) and sometimnes topping the Dmaj with an additional high A works nicely; X00235 (or thumb the low E at 2 for 200235).

There is also a wonderful Emaj alternative that I use sparingly; 022404. It's a little hard to reach this fingering - I usually use it when the chord progresion leads me into it gracefully, but it has a really full and intriguing sound. You can also add the top G# to the Emaj for interesting effect; 022104