All connections should be soldered, not crimped, to avoid corrosion. I went through my whole boat and soldered all the connectors and never had a problem. When talking to others the most frequent electronic failures related to solid state converters for A.C. refrigerators which failed frequently. Also, solid state cooling units had a high failure rate. The best refrigeration units were those where the compressor was run off the engine.
Refrigeration requires a lot of power.
Either engine, solar panels and wind units, or all three. Ice is available all over the Caribbean, though prices vary. Solar power is great down south. GPS, now so inexpensive and reliable, should be considered a must. A good depth sounder and log is a must too for the Waterway etc.