I've never understood why so many people are loyal to multitools. Take a mediocre needle-nose plier, add a handle that cuts into your hand if you squeeze with any force, factor in inferior ergonomics for all the tools and blades that fit in the handles, and what you have is a tool that will do a lot of things worse than a properly designed small set of tools you could carry in one hand.

Just 3 tools and you can deep-six the multitool for 90% of the jobs on deck or in the cabin, and do the work with greater comfort, speed, and with less damage to the item being worked on:

1) A good rigging knife with fid. (My favorite is the Victorinox Helmsman)
2) A Switchgrip plier (see image and link, I've had one for years and it's a great tool, even after being left on deck for a week in the rain)
3) A good multi-bit ratchet screwdriver.

Add the following and you can do 95%
4) 8" adjustable wrench
5) 3M electrical tape (also used as rigging tape)

Add the following and you can do 99%
6) A jewelers screwdriver set (mainly for electronics).
7) Wire stripper/cutters
8) Crimper and crimp fittings
9) Multimeter(nl)