A C-Dory 25 is considerably bigger than a 22. That said, ALL C-Dorys are small boats, compared with the rest of the boating world. So we're talking small boats right?
First, if you thing the 22 bunk is small, think about the rest of the boat. Bill and El cruised a 22 for months, but Judy and I can't. We've been in Journey On for 2 months in the San Juans and Strait of Georgia and that 25 seems very small. But it has a head which gives some privacy, a refrigerator and I can find a reasonable positions in the V-berth with which to sleep with Judy, though there may be some territorial discussions during the night. She's 5' 6" and i was 6' 2". Any smaller boat and we go home a lot earlier. and you need to cut out the V-berth opening. I fought it for years, but it makes all the difference in the world.
The 25 is heavier and bigger to haul. And it needs a 150 HP motor. Worth it, but that's us.
So you have your choice of two small boats: a 22 and a 25. Understand, they're both small. For day trips I envy the 22 owners, but we're cruisers so we need the 25. For a couple of days I'm sure one can put up with a 22 but for a couple of months, it's the 25. At the moment we're in a RV park near San Francisco, visiting kids. I think of that as another good thought for the 25.
So, it's not just the V-berth room but the totality of how you want to use the boat. Worrying about the V-Berth room is just one factor.
Boris