On a recent trip to AZ to see sister and terminally ill brother in law, I got to see/use a Panasonic digital camera my sister just bought.
Not sure of model, but it had a lens equivalent to 300mm and built in anti-shake, which worked beautifully.
We did a day trip to Grand Canyon, and the pics were superb. She took a pic of a deer that was crossing the river. I saw the movement and she zoomed in. I was amazed how far the little camera could zoom

Problem was as you guys mentioned was its size

I don't have big hands or at least not compared to guys much bigger than me, but I couldn't use that camera for the life of me.
I ended up hitting the wrong button or switching modes, which didn't endear me to my sister

I have a old school Nikon waterproof IQ 90 zoom. It's a monster compared to the new digital cameras, but the buttons are large, spaced well, and you can actually hold it with both hands and not take a picture of your finger.
I think if I get into a digital, I would make sure it had a tripod mount and make a homemade pistil grip for it. Maybe a wood dowel, with a finger style bike grip and tripod mount epoxied to it. Something I could hold comfortably in one hand and avoid to many chunky fingers on the little buttons