Our remodel isn't finished yet, but our genius contractor figured out exactly what we needed without our even trying to explain it =) When you reach in the shower, the controls for the shower are on the side wall. We got all hansgrohe fixtures, I don't like rain shower heads, I like a very forceful shower so we got a speakman shower head. Adjacent to that is a 24" bar with a handheld on it, we will mostly use that for washing the dogs. We have 3 large dogs and they are a pain to get in the tub (they get out just fine though,usually when they have soap all over them). We also got a diverter valve.

We did not get any extra jets, I couldn't see any real reason for them, and as our contractor explained the most water you have coming out, the faster you use up your hot water. If we had the extra money we would have gotten one of those instant hot water things, but unfortunately it just didn't work with our budget.

we recently installed a hansgrohe double handle diverter on the side of the shower. one piece controls a hand held on a sliding bar and a rain shower overhead. We turn the water on without getting in the shower and only get in when it is hot.
the only time you get cold water is if you switch from hand held to overhead and then it is very brief and our shower is large enough to stand away from the first rush of water.
I really like the diverter. It controls which shower source, or both at once, temp, and volume.