LH makes a good point. I run a little closer to the shore than you do. That far out you might go above and beyond regular
lighting minimums and flip on the
deck lights. Probably won't bother anyone but the
fish.
That far out you might also send out a quick securite on
VHF on the 20 min intervals. Over the horizon so this also won't bother anyone. Anyone who hears you will want to hear you--obviously not a good plan for nearshore.
I wouldn't call it sleep but I like to run dedicated dual 20 minute
recall alarms with a pair of kitchen timers. On the 20s I would check thru the systems you listed plus 360 visual plus
engine panel. This is in addition to other checks but the 20 minutes is purposeful.
Given the constant checking you might set yourself to be comfortable right there at the
helm. A bean bag makes a surprisingly good, portable lee berth.
This may not fit your plans but I also limit the overall duration to what I can do. I can do 36 hours continuous ops including the 20 minute checks followed by a day or two of downtime at
anchor.
So for me that is out the inlet in the early a.m., run all day, run all night, run most of the next day and in before dark.
Keep your
meals, err snacks, light on carbs, no prep, small and frequent.
I keep a few Red Bull's handy for an
emergency but haven't had to use them.
Own or rent a sat
phone.