Let's go back to the standing rigging for a moment.
ltgoshen, I'm not trying to be an alarmist or anything, but there was recently a thread from another C&C 30 here in the Annapolis area who observed that no matter what he did, his leeward rigging was always way too slack.
The problem ended up being that his mast partners were missing, and his compression post was sinking. I think he had rot at the bottom or something. Apparently this problem is somewhat common to these boats, but it is repairable, and not a boat-killer.
I'm not saying that's you're problem, but take some time and ensure that your mast partners are in place, and in good shape and inspect the base of your compression post for rot or "sinking".
I encourage you to go to the C&C forum and ask about this so that you know what you're looking for when you inspect these items.
As to the question of whether or not your boat is ok for off-shore use, I've pondered this myself about my own Pearson 30, and this is the answer I came up with:
Our boats are either overbuilt coastal cruisers or underbuilt off-shore boats.
They are very tough, which is why it's so tempting to take them so far, but they do lack some structural components that would enable them to take an off-shore pounding and survive in better condition. It's not just the lack of tankage in my opinion.
I'm not trying to deter you, in fact, I say go for it. Just know the boat's weakpoints and limitations and try to mitigate them as best you can.