I have learned after over packing. Keep it light. Only pack cloths that I enjoy wearing. If I'm not comfy I won't wear it. Why lugg it if you won't wear it.
things I always bring:
small night light
small first aide kit
meds, asprin, imodium, pepto, anticid
zip loc bags. Various sizes.
laundry soap in zip lock pre measured
fabric sheets (I toss them in my suitcase. they keep my cloths fresh then I can use them in the laundry.)
extension cord w/multiple outlets