Long wire antenna help

[W9BHI]

I am thinking of putting up a 250 foot end fed long wire.
It will be fed from a 9:1 unun.
It will be strung from the peak of my roof (35 ft.) to a 40 ft. utility pole.
I want to use it primarily for 160 and 75 meters.
Would it do any good to run the remaining 40 foot vertically down the side of the pole to an insulator?
Also, is this a good setup to begin with?
I don't want to get started on this project if it's not going to work well.
Any opinions would be welcome.
Thanks,
W9BHI

[Opcom]

Some people do let the end hang. 40FT is 40FT but it may be as well to stop it some distance from the ground in case it has high voltages on it.

[W3RSW]

Many have remarked that with an end fed wire you need a good rf ground. Kind of what I have here and am probably utilizing a 400 ft. Run of buried, live ac service run for a good part of it since the E gnd and my other grounds are connected at the service entrance.
Maybe noisy?

[K3YA]

The antenna is roughly 1/2 wavelength on 160 and 1 wavelength on 80 and is "voltage fed".   The feed point will have a very high voltage and may present a challenge to the 9:1 transformer insulation.  It may also be prone to RF in the audio or house wiring if the feed-point is near the transmitter.  A short ground connection helps. Keeping the feedpoint away from the transmitter also helps.

Typically such an antenna is fed by a L network, or a parallel tuned circuit with link coupling to the coax.

The extra 40 feet vertical section added to the end will dramatically change the tuning of the antenna and the feed point impedance.  

My first ham antenna was a end fed 1/2 wave.  It "got out" fine.  The feed point and L network tuner were at ground level in the cellar window well with a very short ground connection.  Even with the short ground lead I has some RF issues in the shack and ultimately changed it to a center fed antenna.

[WA1GFZ]

I ran the same antenna as a kid and fed it with an l network. I had lots of RF in the shack. It did work very well off the end on 20m. 80m so-so. a balanced antenna is a lot easier to deal with.