As others have stated, there are several options, of course all based on a price range.
The closer to the beach, the higher the prices, but if you go even a mile or 2 away, the prices are more reasonable.
There are very few paces that are not safe, but some are safer than others for sure! Especially if you want a walkable area.
Some of the loft developments include Uptown Marina Lofts in Aventura, (about 3 miles for beach), Bayview Lofts in Miami Beach (this is actually treasure Island, about 2 miles from beach), The Lofts Downtown and Neo lofts, both in the actual downtown Miami area, and then there are several along the Biscayne Corridor such as Star Lofts and the Yorker.(these will be 3 to 4 miles from the beach).
And that is not to mention and abundance of units that just have double height ceilings and are considered lofts.
So as you can see, there are many units to fit your needs, price and location all to be taken into consideration.
I would be glad to work with you in your search, sending you peopperties to fit your criteria and discussisng financing options.
Feel free to contact me and I look forward to assisting you.
South Florida Brokers