your age and health Boats in the size range you are looking at generally won't offer an aft stateroom if you get one with a cockpit, since you are single the V-berth may be fine.
In fact you can find a 34 foot that is roomier (albeit pricier) than some larger boats. The Corvette 340 has an aft cabin, it is called the "littlest large yacht" (or something like that) there is. If you are new to boating, what I'm about to say probably won't mean much but to others here, it will.
The 34 Corvette was designed by a Naval architect in jolly old E, the company was in business roughly from 1974 to 2009 (or something like that). A couple of senior executives from Fleming yachts fame purchased the company and tooling, and carried over two senior managers from the old company to work with them. The Corvette 340 is built in the same yard as all Flemings. In fact another nick name for the Corvette 340 is "Baby Fleming." You can be guaranteed much feedback from Fleming employees has gone into the most recent Corvettes, video of one below:
What has been done, which I love, is to use the traditional cockpit area as part of the aft cabin and moved the cockpit amenities above. My boat has a cockpit and I consider it wasted space. I have lived in travel trailers and motorhomes so I'm used to every inch of a good build maximizing the space available.
The reason this boat is so roomy is the loss of the cockpit area. I also echo what many have said, by the smallest boat that will fulfill your needs, you won't regret that advise. I have and do look at larger boats and drool, but I'm also very happy with what I have, a 29 foot express cruiser, 50 years old this year, in for a very extensive refit with just about everything worked on, removed and replaced, or added on so that this boat will end up with old bones but new everything else.
This Fleming that's not a Fleming will be more expensive but in my books worth every penny. When you can get more for less, over time it will save you money, from moorage to insurance to maintenance and repair, to the most important aspect, the spontaneity you get from a smaller boat, more likely to go out for a spin with less preparation and crewing necessary.