I recently restored a camper. I decided to put water tanks on top of the camper instead of inside because there was no room for them. I decided to try a gravity flow system instead of a pump system. I installed 3/8 in plastic pipe, non rigid, I connected the pipe to bottom of the tank and then ran the lines to the faucets. There is a total drop of six feet from the tank to the faucet. I can get full flow at the joint below the faucet, about one foot below, but cannot get full flow at the faucet. I have a 3/4 inch vent on top of the tank. When I fisrt turned on the water I got no water at the faucet. I then opened the line at the connection below the faucet and got full flow, but still no more than a slight trickle from the faucet. It was almost acting like I had a vapor lock. Do you think a vent at the top of the pipe line where the water line is connected to the tank would help

Do you think a vent at the top of the pipe line where the water line is connected to the tank would help You've already vented the tank so that should be enough.
If you have full flow at the supply, ( you should have a little over 2 1/2 PSI) and slight flow from the faucet then I'd be giving that faucet a good hard look. Good luck, Tom