Sunshine,
I had a dive buddy along, so shore diving anywhere we could get to conveniently was not a problem.
It's a long story, but OE East told me about the afternoon boat dive to Watumula at OEW, and I told them to book it for us on any day. They called OEW for me and were told they didn't have an afternoon boat dive, so I didn't pursue it any further.
On our last day on the island, I dropped in at OEW just to look around and saw the afternoon boat dive listed on the board. I asked about it and was told there hadn't been any demand for it (probably because people were doing the morning dives instead) and it hadn't gone out all week, except for the snorkeling trip.
The clear, flat water and beach at Playa Kalki are beautiful. It is night and day compared to anything close in to Willemstad. I wish I had gone that far out west earlier in the week.
As far as activities for non-divers on Roatan vs Curacao, I guess I need to qualify that. It depends on what interests you. When you list all the available things to do in each place, my non-divers found more things that rang their bell in Roatan than Curacao. Even so, they were still busy all day, every day. They definately were not bored.