Garelick makes a variety of boarding ladders, including three step versions of the ladder Steve uses. His boat only draws 9" loaded, so a longer ladder isn't really workable in shallow water. I am 64 and tape-in at 6'-3" and 237lbs., currently. And, no, the Whitehouse physician is not my doctor... As Steve already stated the approach angle is adequate to enable deep water access, even for me with an artificial right knee and fused T11-L1 vertebra with intact rods in place. I rigged a single rung weighted rope ladder for my TDB. At depths over waist deep water using it to access the boat is very difficult, but achievable. In a man overboard situation, if I was alone, probably impossible to achieve, so I tether myself off when hunting alone.
http://www.garelick.com/Boarding-Ladders
In 40-45F water, you have about 5 minutes to save your life by getting out and back onboard, which minimizes your danger... but does not alleviate it. If you are overweight you may last longer, but if that weight gain is concomitant with cardiovascular disease, high BP, cardiac conduction issues, etc. I would make a point of either not going out in rough weather cold water conditions on open water or tethering yourself off on a short line when moving about. Immersion in cold water, for any duration, will spike your cardiac preload via a massive constriction of your arterioles, significantly raising your blood pressure as well as significantly increasing your risk of a sudden cardiac death event. I have a friend who had to tie his best friend and hunting partner to the outside of his duck boat and run him across about 3/8 of a mile of open water to a waiting ambulance because he could not get him back on board their tender when he flipped a duck skiff over while reaching for a bird. He had stopped breathing, but the EMTs worked frantically on him, hoping to revive him. He quit carving and duck hunting following that tragic accident.
On a brighter note, I just received delivery of a five panel replacement blind for my TDB-17' Classic. I was able to steer Olsen Marine, Inc. to a source of Mil-Spec. Brady Amendment Compliant 1000D Cordura fabric prior the order placement, so this is one of the first blinds made using the new fabric. I have five other 1000D Cordura mil-spec swatches for comparison. This fabric is essentially the same in terms of weave, but the urethane coating is significantly thicker than all of them. Very nice construction quality and well thought out additions to my old time-worn version. During a follow-up conversation with Tom Olsen I asked if he would be interested in feedback from Duckboats.net members on interior design and set-up on the new TDB-21' Sea Class they are about to start production on. He said he would be open to suggestions on layout and standard features to incorporate into the build. Tom said he would attempt to post their build sequence both here and on their Facebook site for the first four pre-ordered boats that they are about to begin on, since these are custom orders. Other than a steering console for the wheel and throttle/shift control binnacle, interior lights, bilge pump and decoy storage capacity, the interior is a "clean slate".
My first two requests would be a Richie compass with lighted bezel, mounted on the steering console, and a maximum capacity bilge pump operating off a dual battery switch wired to a deep cycle house battery and a cranking battery, both in the group 27 size range.