We added an arch and radar to our C Dory when we got to Mackinaw City during our loop. I was concerned about the trip down Lake Michigan, but we never needed it for the remainder or our trip, which ended on our return to Albany, New York
I'm guessing that, to get from Carrabelle on the Florida Panhandle to Tarpon Springs, you travelled only in daylight using the Carrabelle-Steinhatchee-Crystal River-Tarpon Springs route, and not the 170-mile overnight route directly to Tarpon Springs from Carrabelle. For those - you would not have been - concerned with their boat's deeper draft, the choice is almost always the 24-hour overnighter. I assure you, having radar aboard was useful and a great comfort.
Although most who make the crossing don't encounter much of anything overnight, twice we had boats cross our path about one-half mile in front of us. Given that, at the time, we were pitching significantly, sometimes violently, there would have been a good chance that we would not have picked up their running lights. Standing at the lower helm it was all I could do just to hang on never mind trying to discern running lights from the lower helm station through the dark and wet windshield. Being able to sit down and simply monitor the radar screen was the best I could do. It worked. Those two boats appeared as big, obvious targets moving across our bow.
We are in Fort Myers now having started our Loop last May from Annapolis.
That nighttime crossing was the only time we needed and used the radar but we were sure glad we had it that night. That said, a 32-foot sailboat left Carrabelle at the same time, no radar. For a time, earlier in the night before the heavy seas began, we could see his running lights about 2 miles off but he did not appear on our radar. He obviously did not reflect radio waves being small, low profile, and having no radar reflector. Very risky in my opinion.
If my guess was incorrect then, well, my experience is my experience and is offered as another data point. My wife was frightened that night. I was not but I was concerned, aware, and vigilant. If you had been out there that night in your C-Dory, it would not have been pleasant. As it was, even in our stabilized DeFever 44 weighing 54,000 pounds, it was a rough crossing. Having radar removed one very big concern from the overall.