which racing dingy to start in the ocean?
My current favorite small one design keel boat is the J-22. At least here on the Atlantic Coast these are one designed raced at a high level and yet you can race in the class even as a novice. There are so many around here that it is easy to get someone to give you advice and a leg up. I find these challenging boats to win races with and yet ever sail seems to teach something. Most are pretty stripped out down below but they have a flat where you can rig a small vee berth.
I would also check with the local fleets and see what is raced locally. Santana 21''s used to be popular out there as were Ranger 23''s but that was a long time ago so I don''t know if these classes still exist.