Not sure how long your get home trip would be, but considering the noted terrain, I'd make sure I have:
- Machete
- Wilderness FAK (bites, trauma)
- Bug net
- Sturdy waterproof sack (can be used as a floating aid, I don't trust garbage bags on that)
- Water filter (Sawyer - my choice)
- Dust mask (or even a gas mask, as an EMP will create some radioactive waste in the air anyway, so if you are serious about that some iodine supplement is also a must)
- A better spirit compass to work with the map
- Spare prescription glasses/lenses
- Fishing supplies?
- A gun?

For the routing, I'm not local, but perhaps that smaller boat could be re-rigged for paddling or even basic sailing as a need arises to cut the land trip a little? Then some arrangements to speed up the transformation could be made in advance.