Well, here's what I've been wanting to try for years, but the closest that I've gotten too was to shunt-feed a tower. My plan is to build a raised VERT dipole on 40M in an +80ft pine tree. However, I don't have an 80ft pine tree where I am here, but did up in WNY. The idea was to run the VERT radiator and radial mounted to the whole trunk of the tree. The few problems that I foresee here was the GND affect of not having that elevated GND radial high enough. That should actually be more of a problem for TX and not RX. S/N Ratio would be increased going VERT, so ideally having such an antenna as far from the power lines and the noises of the house would be good. NVIS closer-by stations would be harder to DX, so the HORZ dipoles for them, but European, Pacific, and Latin American, DX should improve significantly. (Lazer Hot Hits would be a good tester for this.) To reduce static build-up, a 1K-Ohm resistor between the radiator and radial would be a good idea, albeit it may go POOF with a close lightning strike. RG-6 is certainly not a problem for RX'ing, albeit your feed point would be elevated +40ft in a dipole situation. Sounds like you have a Balun already in mind for the slight miss match. (For RX, I wouldn't even worry about that.) If you went the 1/4-wave over GND based radials, the question is on RX only if the more radials, the better? I can tell you that just using 4 radials on the tower shunt-feed may not have been enough on TX'ing. Stations on MW, 160M, 75M, and 40M, were very good, like S+20/9 RX'ing, but getting back to them was doable, but I was told that I was weak. So, more elements for GND radials would have helped me there, but in your case 3, or 4, for just RX'ing maybe enough. As far as GND radial wiring to try? I was using AWG#10 solid copper, leftover from a 500ft spoil that I bought in the early 1990's. (Yeah... I've made a lot of antennas from that, as well as gave away a lot of it.) Aluminum should work fine for the GND radials. Never tried steel, but I don't see why that wouldn't work. And, a parasitic reflector? Hmmmmm... Do you have a close-by tall tree to run some metal element up and mount too? (Wishful thinking, but...) Finally??? Even though you want to dead-nuts match this VERT at 43M, you may find that it should be decent from MW to 30MHz, especially with an antenna tuner, but even without. So, good luck on this project! Just let us know what your results are after you get that going. I'm still going to wish for that +80ft tree to use for mine. Just my $0.02 worth.