Thx everyone for the input. I have learned a lot... here's what I understand.
The geometry and fit are the first priority, so that I am not bent so forward as to always stress my neck. Dropdown handle bars that support this are better than flat bar because of varied hand position/less wrist, elbow ache. The design of the handbars and how my hands fit whatever it's called where the gear/brake levers are is also important. Limited pressure on the wrists is important, which also has to do with using my core better.
The next thing is the size of the rear cassette - how many gears there are, mainly so that there are really easy ratios for uphill after a long ride. I don't know if I want a single or double chainring, but at least I know to ask and explore. Going back home on my bike after a long ride on beach route is all uphill and I want to expand into more hill riding. But my base ride is along the beach and is flat.
Seat will take some experimenting. So will fit, maybe - buy the bike at a place where I can really test it (eg, the shop I went to yesterday let's you rent a bike for the weekend and apply the price to purchase.
I am not sure how much I really want carbon and the best components. A lot of what I read about more expensive frames and components is they are for performance at speed and I am more interested in being able to ride for extended time. That said, really snazzy bikes are cool. (But what I learned in golf, after playing a lot of the 'best' clubs is I enjoy older, classic designs that are 1/4 the price).
So, now I feel like I am informed enough to have a fighting chance at getting something I will ride and enjoy. So I really appreciate you guys all sharing your insights.
PS: what's the deal with 5 posts in a 24-hour period? Is that just because I am new (which makes some sense) or is that the way it always is?