"Winterizing" your ride

A good thing for new folks and a reminder for experienced is that fishing in fall and winter has the potential to create some new and exciting issues. 
First, really consider a compass. Fog in the salt can come down REALLY quickly, and if you haven't been out when you can't see land, it's interesting and nice to know which way to paddle when ANY shore is a good shore.  Phones are good and a VHF (charged) floater radio is great, but so is even a cheap compass telling you "go east!" or toward shore.   A whistle, small flashlight and knife are good and may be required.
There are fewer boats that might offer assistance and it's nice when the yak floats if you do roll and maybe can't get in, or an open hatch (danger) fills up as you're stashing things.   The Trident 13 has hollow space in back I'll never use that tends to collect knives and things sliding back from the center hatch while loading.  Stuffing some styrofoam provides a lot of flotation and also keeps my gear from hiding.  I started using old PFD's, but the material retains moisture which turns to mold.  I can beat the Styrofoam out if that happens, but it hasn't.  I also keep an extra PDF that weighs nothing in the front hatch near the battery bag just in case.  Again, weight concerns me, but these items weigh VERY little and are worth it to me.
Other gear such as immersion suits are mentioned a lot, as they should be, but there's some small things that can make a difference.

I'm a big fan of my ritchie compass.  I've always carried redundant compass, but having it flush mounted on the bulkhead has been really nice.  I fish out of sight of land reasonably often.  Last month it started blowing S about 20 and the launch was about 5.5 miles SE of our position.  At it's worst, I was still losing ground according to my GPS but I was pointed the right way according to my compass.  If you are just relying on GPS you might have a problem.

Lastly, always know what way the coast you want to land on is, never just assume that it is to the east.  Launching around capes and heads, you may need to go north to get home.  Land may be quite a ways to the east.  You might get there eventually, but nowhere near your vehicle.

If this wasn't posted in the safety section I might have just let it go, but the pictured flotation example is asking for a Cleopatra's needle scenario if this boat was to be swamped. Those who have read Steve Hutchinson's work will recognize the reference.

This is a good article regarding Cleo's needle and the solution.

http://www.useakayak.org/recoveries_rescues/cleos_needle2.html

Flotation should be secured and balanced throughout the boat.
The ideal state is 0 dead space.

The last photo is a nice example of a SOT in needle mode.

Good point to bring up. 
I did mentioned I keep an extra PDF up in the front hatch (there are actually 3 up there) so I'm satisfied I'd have some semblance of balance.  It may not be the:

The ideal state is 0 dead space.

, but I trust it will be me from being dead with the other precautions I take.  The ideal state for pure safety is likely on the beach.

Again, nice catch and comments.  I've seen a few SOT's out with no flotation as folks don't think about the "what if" and get to feeling they're paddling an unsinkable cork.

Something that I practice, that takes up the remaining dead space, is keeping my dry bags fully inflated no matter how little gear I have in them. A fully inflated dry bag gets double duty as flotation and gear storage.   

Notice that some of the pool noodles are hollow in my boats. This allows the use of a small piece of 1" pvc to attach 2 pool noodles together and run the full length of the hull. I need to cap the ends with a ping pong ball to get max flotability.

I used to use a dab of goop to secure the pool noodles to the hull. That was a mess and made removal challenging. Now I use velcro stickers that are used to hang picture frames for smoother ops.