So, would they be ok to sail across the stream to the Bahamas? Across
the Northern Gulf back and forth to N or S. Florida? Down island to
the Caribbean? What are the limits?


Many have done it very successfully.
Your reasoning is sound, the only thing
missing in the Mac 26x is the ability to sail
a wide variety of conditions, weather needs to
fit more narrow parameters for good performance
and sailing pleasure.
But then it's a motorsailer NOT a sailboat.

Glenn