Electronics update for cruising

[travalab]

So we are looking at possibly purchasing a boat, the current electronics package is this:

Two Raytheon radar systems, one antenna on mast, the other on a pole in the cockpit. Raytheon C120 GPS/plotter at nav station, C80 at helm, two Furuno GP-32 GPS's at nav station. Simrad AP 16 autopilot, Brooks and Gatehouse apparent windspeed/direction indicator, depthsounder, knotmeter/log, all (2006) mounted on pedestal guard. Ritchie pedestal-mounted compass. Icom IC-M700 Pro marine SSB transceiver, two Icom IC-M304 VHF radio transceivers. Icom CommandMike2 RAM. ACR Sat 3 406 mhz. EPIRB. Firdell Blipper mast-mounted radar detector. Backstay insulated for use as SSB antenna. Spare VHF antenna mounted on radar pole.

Looking at this setup, what would you recommend updating? The plan is to use this boat for cruising the next 5 years, hopefully extended cruising but for sure New England, the Bahamas, and Caribbean.

Is it worth starting what the boat comes with and upgrading the particularly antiquated parts, or is it best to tear everything out and start new?