One of my sailing buddies was upset because he about to head off on a cruise, and his boat was not ready. Lot's of items on his to do list. We came up with the following prioritized list, and off he went, with a number of "small" things still not working. He had a great time.
Here's the list:
1. No Leaks - if the boat leaks and sinks, pretty much any thought of having a good cruise is out the window (I guess small leaks are OK). This item also encompasses common sense stuff like the keel should stay attached.
2. Rudder - If you cannot steer the boat, what's the point. Also, had a buddy loose his rudder about 500 miles from anywhere on the way to Tortola. Hard to go in straight line with makeshift stuff.
3. Rig - If the rig falls on your head, you cannot sail. Sails need to be reasonable too, but the rig needs to stand or the sails are just interesting hunks of synthetic fabric. Yea, I know someone will tell us a story of a makeshift rig across an ocean, but if given the choice they'd rather not.
4. Anchor - Need to stop once in a while in places where it's shallow enough to find the bottom. The closest thing we've got to brakes in a car.
5. Engine - Case the wind dies, and we aren't skilled enough to sail into any marina in any wind condition (although I understand many sail netters are, so good for those who can).
Yea, I'm assuming you've got safety gear, meet the CG regs, etc. Goes without saying.
But when you think about it, everything else is just about added comfort and convenience. If the winnebago stuff fails, you can find a way to keep going and fix it later.
Pressure water fails - foot pump
head fails - bucket
fridge fails - ice, in the UK they like warm beer?
ac fails - leave the marina, anchor and open the hatches, go swimming
audio system - talk or sing
radios - be self sufficient for a bit, miss the daily net gossip
chart plotter - paper and eyeballs
depth sounder - lead line
radar - stay put till the fog lifts or nav the old way
wind instruments - wet your finger and hold it up
Yea, I like having all that stuff work too and there's plenty of strong opinions on what safety gear you need, all the way from those who won't go anywhere without a personal rescue copter at the ready, to those who say I'm on my own in the wet wilderness.
But it's hard to have a good cruise without the high priority items working
Do what I say, not what I do. Get the priority stuff right then go! Sounds like you've got quite an adventure on the horizon.