My advice: narrow the aperture and increase the depth of field on all these. Use a tripod, or increase the ISO if you have to, a greater depth of field is worth the price of slight graininess.
Also, on photo #1, you probably want to set the white balance on your camera to the light bulb. Play around with that until what seems white to your eye seems white to your camera. Other than that, you got the focus on the eye, which is good, but it might be more dramatic if the camera had been at eye level with the cat.
#2 I like quite a bit, quite moody. My only CC is to consider the focal point a bit more, and increase the DOF to get both flowers in focus.
#3 the biggest concern is making sure the center of the flower is in focus.