??? For the Older Guys... Retirement, What am I missing.

[blktoptrvl]

OK guys. I respect the opinions of most of you and wanted your input on this subject if you are older than 53.

I am 53
I am thinking of retiring at 56
I owe nothing except for monthly utilities, insurance, food, projects around the home.
My retirement plan is fully funded for a comfortable annual income until I die.
I expect to live until I am 75 at the latest.
I have planned my retirement to provide income until I am 90 (just in case)

I have a full set of tool in the garage along with my 4 cars - which I can foresee taking me to the end. I may work maybe 2-3 months a year for the 6 years after I retire so that I replace current expenses (until official retirement) and afford toys: I am in the process of building an airplane, I may purchase a used motor home and roll over the entire US.

I understand that I have no control over health issues and if I get hit by an unforeseen medical issue all my plans could go out the window. I am putting a new 25 year roof on my house this year.

So, what, if anything, am I missing that could derail me? This is where I am looking for your input. Were there any surprises that you didn't think of?