Yes, I often do that even with my better camera/lens shots. Many really need it since I'm mostly shooting RAW anyway. A levels color adjustment in Photoshop alone (resetting both ends of the histogram for each component color) works wonders for color and the contrast and clarity slides in Adobe Camera RAW or adding a slight "S"to a curves layer for contrast in Photoshop also helps.

The only images that rarely need much sharpening for the web are those from the Foveon sensor (DP2 camera). They are tack sharp right out of the camera.  

I can swear there ain't no heaven but I pray there ain't no hell. _ Blood Sweat & Tears