Class C for a tall person

At 6'4" I have plenty of headroom in my 2016 Itasca Navion 24G, built on the Mercedes Sprinter 3500 chassis. The main selling point though was the driver's seat room and comfort. I can actually put the seat back too far, something that was impossible in any of the Ford or Chevy based Class Cs. I can also easily move from the driver's seat to the living space without contortions, again something I could not do in the other ones with the big doghouse protruding from the firewall. The rear bed is a little short but it's a "walk around" and I can comfortably hang my feet off the end like I've been doing on most beds since I was 16 or so.

I'm technically 6'2" also (although I think I've lost an inch, worn down by almost 70 years of fun), and I have no trouble in our 2007 Itasca Navion; it appears to me the model hasn't changed much in the years since ours was built.

In fact, we rejected a lot of the RVs we looked for that reason; stepping into the Navion felt quite nice.

I found my C has more headroom than my A, and most As for that matter. I am 6'5", and can easily walk around in my 1980 Minnie Winnie, whereas my 1995 Safari Continental found me hitting my head on lights and the AC.

I believe that space is a subjective issue. I am 6'2" and fit fine in my Leprechaun. Other people might have a different opinion. In my experience, space needs have to do with other issues other than real space. MHO

My Nexus Ghost has a 84” ceiling height.

Speaking only for the cab, the Sprinter offers the most space by a wide margin, and the chevy is better than the ford by a small margin. Another big factor, is when you test out the driver position, make sure the slideout is in. When I was shopping, the slideout in every single ford and chevy chassis rig restricted driver seat movement and I couldn't move the seat back far enough for myself, even at a short 6'0". The sprinter carries its own set of issues. If nothing mechanical goes wrong it's great. When something goes wrong, service is more expensive and harder to find. I do like getting 16 mpg with the sprinter, knowing full well I'll never break even with the extra upfront chassis cost. Like almost everything else, it's all a big pile of priorities and compromises.

Cross off the Phoenix Cruiser from your list of considerations. The limit on height for any adult is 6'-0" with consideration for shoes.

The Phoenix Cruiser has a lower over-all profile. Mine is 9'-10" to the tippy-top of the a/c unit which is very hard to find in a class B+ or C. I know because my garage door opens to exactly 9'-11.5" leaving me with just 1.5" to spare.

It has been real nice to drive around knowing all the taller rigs have broken off all the low hanging branches. :) That along with better aero-dynamics for improved fuel economy and better handling. But hitting my head on the a/c duct all the time, would surely nix all that....stay away from the Phoenix Cruiser for every model has the same interior ceiling height.

What IAMICHABOD said.
I am 6'5" with a Thor Class C. The problem for me is not the head room - it is driving comfort. I have plenty of head room in my camper, and it is very comfortable to drive. The trade off for me is comfort vs. fuel. Mercedes is diesel. I prefer a gas engine. We try to avoid freeway travel vs. back roads and diesel takes a little more planning ahead to locate stations that have diesel.

At 6'6" my Tioga has plenty of head room,I found that most Class C RVs I looked at had adequate head room.

The real problem for me was the drivers area,the cockpit of the ones on a Ford Chassis were just to cramped,and almost impossible to drive comfortably for any length of time.

I chose one on a Chevy Chassis for that reason,another thing to think of while shopping for your next RV.

Depends what you want. Renegade Dynamax Nexus etc all have 7’.