Check the post of WA5YOM about his experiences with an OFC vertical. I would run from that idea. What you have have is much better than a 24' OCF vertical. See the forum Antennas, Towers and more, Greyline Vertical issues.
So, what to do about your RX noise problem. Noise outside your house is often out of your control but you can improve things. What bands do you want to operate?
You say you have a 34 in magnetic loop in the back yard, but on 160 it’s not great.
Does that antenna help on the higher bands?
Does it have a mast mounted preamp?
Can you build a larger loop (like 2X the size) for 160 meters?
Two of several methods to obtain a better RX S/N ratio:
1) A rotary small loop antenna mounted near the ground such as you have
2) A phasing box and sense antenna. Your loop can be used as the sense antenna. DX Engineering stocks boxes by DX Engineering, MJF and WiMO.