Features and Ergonomics
There is much more to ergonomics than the size of a radio, the size and number of knobs, or what the radio looks like.
Software Menus: Most of today's radios have software menus. Some manufacturers use plain text and abreviations for their menus, while others use strange codes (combinations of letters and numbers). Some radios, even new ones, have no software menu at all. Each person must determine for himself (or herself), which method (s)he is comfortable with.
Features: Most radios have far more Features than anyone actually needs or even uses. If you want to argue this point, then my reply to you is, you are the exception. If it's features that intrigue you, then by all means buy a radio with lots of knobs and lots of features...but that doesn't mean you will be buying a good radio. A summary and explanation of all of the possible features of radios is beyond the scope of this web site.
On the other hand, Ergonomics can be important to many people. If you are older (like me), you probably have difficulty seeing small things or spinning small knobs. A larger radio may be a better choice for you, even if it does not have as many features as another radio that interests you.