Re: Hawaiian shirts
Aloha, aka "Hawaiian", shirts (which were actually invented by a Honolulu-based Japanese retailer and initially made from kimono fabric, according to Wikipedia - you learn something new every day) and their cousins the guayaberas are my preferred summer wear, too, when I'm not doing manual work on the house or grounds. Loose-fitting, breathable, decent sun protection for the covered areas, and more interesting than the typical print T-shirt (or, god help us, logo-bearing polo shirts). And they usually have a handy pocket or two.
At the beach, after coming out of the water, an aloha or guayabera is a lot easier to throw on than a T-shirt. Leave it unbuttoned to protect the shoulders and back of the neck from sunburn while letting the breeze dry you.