Check out the Thrane&Thrane Sailor Iridium Pilot (ex OpenPort) data and voice comms sytems. Around $5k for the terminal which provides phone and 100kbps-ish internet.
If you need more than that the FleetBroadBand 500 has been very solid for us but the terminal is $16k and data is $9/mb.
Raymarine's new NMEA2000 (seatalk ng) equipment is pretty versatile, but the shiny new E series gear is not very rugged. The C90 is still available and is a solidly built performer. Raymarine also just announced class A and B AIS transponders. Handy having all the sensors on one network, all feeding blended data to all of your plotters.
Stay away from Garmin RADAR. They emit a lot of noise and interfere with VHF. They're priced where they are for a reason.
Standard Horizon GX5500 DSC radio is affordable and works. I run these on west coast 'hard use' vessels with a totally reasonable failure rate. Don't skimp on the coax. It's worth it to pay for LMR200, RG223, or RG400 for your main VHF antenna run, and don't ever ever use those crap Shakespeare compression RF fittings.
EPIRB is nice to have, but someone's got to come looking for it to be of real use. Many parts of the world don't have any real SAR capacity, so its utility becomes a bit moot.
Spot or an equivalent may be a better choice, depending on where you're going, and who you want to keep updated.
Cellular modems and the newer integrated hubs are handy if you've got a good data plan. I've had good success with the 4G NETGEAR MVBR1210C Turbo Hub on littoral vessels. These offer both data and a phone port.
If you do the wifi thing, consider putting a well sealed Ubiquity BulletHP on an antenna up the mast. Very cheap and surprisingly effective radios.