Believe your own signature. Attitude is everything when it comes to survival.

Some things I normally carry as a matter of course are:
All this stuff is waterproofed in separate Zip-Lock bags and inside a water-tight plastic box.
A flashlight (in addition to the headlights on the bike)
Marine Hand-Held Flares x3
Signal Mirror
Wind Storm Whistle (very loud, not waterproofed, but supposed to work underwater)
Pocket Knife
Lighter
Roll of Toilet Paper
Bicycle Multi-Tool
Tube Patches
Spare Tubes (for the bike and trailer)
Pump (can double as a bellows if a fire is needed)
Zip-Ties, Assorted
Water (very important in all conditions)
.357 Magnum (sometimes) (if you're in bear country a .44 Mag or bigger would be better)

I don't carry all this specifically for cycling, but for other things I do that take me off the beaten track.

In cold and remoteness like you're describing I would also carry a change of dry clothes and boots, in case you have to walk out. At least one of those space blanket things, if not a sleeping bag.

And you might want to consider what you are going to do if you crash and are injured and immobilized. A small tent or bivy bag, maybe? Might want a backpacking stove? Candles are always a good idea in cold weather. Maybe a couple of those Hot Hands type heater packs?

You said you weren't concerned about speed or weight. Can you tell I usually tow a trailer?

Hey, here's the best idea. File a "Float/Flight Plan" with someone. You should be able to do this with your local law enforcement if you don't have anybody else. Tell them where you are, when you're leaving, your route, when you expect to arrive at your destination and that you will contact them when you get there. That way if you're late somebody will know and have some idea of where to start looking.