I would repaint the kitchen walls, change the countertop & backsplash, maybe hang lighting over the island - before even considering painting the cabs.

I agree with mdln. While painted cabinets seem all the rage on HGTV, the reality is that stained cabinets are also lovely and mid tone wood is coming back. I recently changed out my countertops and installed a new backsplash and farmhouse sink. I am very happy with with the refresh. (pictures in my "my pics" idea book - my kitchen is a cottage / French Country style.)

If you have your heart set on painted cabinets, look into the cost of a professional paint job. It is a bit pricy. I do not recommend painting them yourself unless you are an experienced and patient DIY person. It is an arduous task and since cabinets are expensive, messing them up would be costly. Whether painted professionally or DIY, a painted over stained cabinet will not have as durable surface as a factory finished cabinet. Your cabinets look to be maple, and maple paints up well, so that is a plus, but wood does move with changes in temp and humidity which cracks the paint at the joints - so occasional upkeep might be necessary. Most factory painted cabinets are MDF or a combination of MDF and wood because MDF is more stable to movement. I don't say this to deter you - just to make sure you are aware of possible problems. Many people paint their cabinets and are very happy with them.

I would not advise you to go gray. Your home probably has a warm color pallet based on the warm wood tones of your cabinetry. It is very difficult to mix warm wood tones with cool gray. The result if often drab. Gray belongs to the white / gray / black pallet which is why you see it paired mostly with white cabinets or sometimes very dark wood cabinets. If you paint your cabinets gray then it is possible the kitchen will not be cohesive with the rest of your home. I have seen homes which have redone the kitchen in gray and walking into it is like walking into a different house. Some go on to change the rest of the house, at great expense - which is fine if that is what they like and can afford, but it will likely be out of style again in 10 years.

If you paint, white/cream would work better with your warm tones and allow you to refresh without committing to a whole house remodel.