What is the difference between a coastal crusier and a bay b
I am not exactly sure what you are asking because the question was truncated. When I think of a coastal cruiser, there are a number attributes that I look for:
Good wide berths, at with enough seaberths for at least half of the crew. Good storage to accommodate the larger crowds that is more likely to cruise on a short trip. I am looking for a well-equipped galley that has adequate space to prepare meals for a larger crew or a raft-up. Refrigeration is less important.
A comfortable cockpit for lounging is important. It should be larger than an offshore boat to accommodate a larger number of people which is OK since pooping is less likely to occur doing coastal work.
While gear for offshore boats need to be simple and very robust, coastal cruisers need to be able to quickly adapt to changing conditions. Greater purchase, lower friction hardware, easy to reach cockpit-lead control lines, all make for quicker and easier adjustments to the changes in wind speed and angle that occur with greater frequency. There is a big difference in the gear needed when ''we''ll tack tomorrow or the next day vs. auto-tacking or short tacking up a creek.
Keel and Rudder types:
I would say unequivocally that a fin keel is the right way to go here, The greater speed, lesser leeway, greater maneuverability and windward performance of a fin keel with spade rudder (either skeg or post hung) are invaluable for coastal work. In shallower venues a daggerboard with a bulb or a keel/centerboard is the way to go
Good ground tackle and rode-handling gear is important but all-chain rodes and massive hurricane proof anchors are not.
At least on the US East Coast, (where I sail and so am most familiar with) light air performance and the ability to change gears is important. It means more sailing time vs. motoring time and the ability to adjust to the ''if you don''t like the weather, wait a minute'' which is typical of East Coast sailing. If you are going to gunkhole under sail, maneuverability is important. Windward and off wind performance is also important.
With all of that in mind I would suggest that a fractional sloop rig with a generous standing sail plan, non- overlapping jibs, and an easy to use backstay adjuster is ideal. This combination is easy to tack and trim and change gears on. I would want two-line slab reefing for quick, on the fly, reefing. I would want and easy to deploy spinnaker as well.
I think that speed is especially important to coastal cruising. To me speed relates to range and range relates to more diverse opportunities. To explain, with speed comes a greater range that is comfortable to sail in a given day. In the sailing venues that I have typically sailed in being able to sail farther in a day means a lot more places that can be reached under sail without flogging the crew or running the engine.
Good ventilation is very critical. Operable ports, hatches, dorades are very important. While offshore small openings are structurally a good idea, for coastal work this is less of an issue.
-Visibility and a comfortable helm station:
You are more likely to be hand-steering in the more frequently changing conditions found in coastal cruising and are more likely to have greater traffic to deal with as well.
These are my first thoughts on this topic.