[CA] What else to buy

[Rettirc]

Hi I need some help, I am updating my sailboat and want to ensure that I order all required cables, devices etc. I shall be fitting the equipment in a fairly remote area I want to ensure that I have everything, it has been hard to establish exactly what is in each box.
I am going to purchase:

2 x Axiom 9" MFDs 1x inside, 1x outside
EV-400 auto pilot
Quantum radar with 15m pwr and data cable
I50 &I60 Wind/speed/depth value pack
2 x I70 multifunction displays. 1x near i50&i60. Other 1m from inside MFD
AIS undecided, leaning towards Vesper xd8000 for anchor alarms, suggestions welcome, like the idea of this being WiFi.
Have B&G V50 radio, would like to connect to network. 1m from MFD

What additional cables, devices shall I need?

I am debating whether to get one Axiom with the down-vision option, should I worry about this feature? The only reason for this is if I want it upgrade sonar later??
Is there a possibility that in the future there could be a forward looking sonar? Would that warrant getting the downvision option?

Thank you in advance.
Chris