The 18-35 is a fantastic lens! Stick with that and go for a .71x speed booster if you are planning on using APC-C lenses such as the 18-35.
When I got my P4K I had a job coming up soon after. I couldn't get a Metabones adapter here in time so ended up buying a Viltrox as an interim adapter for the job. That job was a car commercial and we used the P4K as a car mounted B Cam and for gimbal shot's.
The images looked great, I never bothered getting an actual Metabones adaptor, the Viltrox adaptor has not left the camera body and the camera continues to get used as a B-Cam to FX9, Alexa Mini, UMP etc etc. The Viltrox is about one fifth the price of the Metabones.
If you are going to only use full frame lenses, get the .64x Metabones and if you are going to use super heavy lenses, get the Metabones with the locking EF mount although I have put cine lenses weighing up to 1.6kg on my P4K with no issues.
If you want/need a super light and small rig, maybe consider native lenses but i'd recommend trying the lens you already have (18-35) with a Viltrox first. It's a killer combo! A slightly heavier camera is less susceptible to micro shakes when hand held.
Simplest thing to do here is have a safe workflow when setting and taking down your camera rig. In the example where you have a camera and a recorder/monitor both receiving power from the same power source, yet have a high frequency connection between the camera and recorder/monitor like SDI 6G/12G or HDMI 2.0/2.1 and unshielded cabling is used. Simply following:
- When connecting: FIRST connect power cables, THEN HDMI / BNC.
- When disconnecting: FIRST disconnect the HDMI / BNC, THEN the power.
Also helpful is using shielded power cables and avoiding D-tap connectors (since they can possibly be plugged in backwards). To safeguard your D-tap connector you could add the Lentequip Safetap which protects against reverse polarity, over/under voltage, and short circuits, as well as preventing battery deep discharge.
But just following the connect/disconnect process above should protect you most of the time.