Sailed 445 Beneteau with a 6''9" draft up HawK''s Channel with no problem from Key West to Monty''s Marina in Coconut Grove.
Yes there are shallow areas but the charts
Angel Creek Pass entrance into Biscayne Bay was a bit scary when we got hit with a downburst. Did not touch!
The Holiday Inn Marina on Key Largo lists the entrance at 5'' at MLL. We sailed in at high tide following a local with no problem had to sail out with the tide when it was flooding.
Holiday Isle Marina also lists 5'' at MLL but it it is passable at high tide.A great clue is that when the tide is out there is a party on the sand bar with a number of boats.
Great anchorage at Bahia Honda State Park you need to enter through the old train tressel that was cut plenty of room and it shows 7'' all around.
Just check your charts
watch the tides and keep in mind that the depths marked are listed at the mean low low tides.
I never touched, the word is! trust your depth finder and know your vessel.
All the entrances I listed have sandy bottoms.