There are the 'ideal' things and then thre are the 'practical' things. The 'best' things are the best compromise you can make with both of those 'things'.
The ideal.
The ideal set up would be a perfectly resonant and matched antenna connected to a perfectly lossless and matched feed line connected to a perfect transmitter. With the antenna as high as humanly possible on a non-metal structure that's perfectly transparent to RF. That'd be great wouldn't it? It's also perfectly unlikely to ever happen.
Now for that 'practical' thingy.
Do the best that you can do with what you have available to do that with. Which opens all kinds of possibilities and problems, right? Oh well, that's the way it goes sometimes.
Metal pole versus non-metal pole. It really isn't that important as long as that metal pole doesn't detract much from the antenna's performance. That's controversial, so the best thing I can think of is try it with the metal pole since it's already there. See what the average results are. Other wise you have no basis for comparison.
How high should an antenna be? As high as you can make it until you can't reasonably make it any higher. Lots of 'wiggle' room with that one. Isn't a matter of what's -possible-, but a matter of what you can do without bad consequences. Those consequences include $$$, tearing up the house, the significant other's opinion of the whole thing, neighborhood association, and getting to the point of "How the H@## do I do that?". If that means below roof level, or just at roof level, or slightly above roof level, that ain't bad for a start. You have a basis for comparison later.
The shape and/or type of antenna.
Pick one that has the characteristics that you think will be useful. First that comes to mind is polarization, vertical/horizontal. Next is, where you gonna put the thing, and can you, will it fit? How about 'gain'? Gain ain't all it's cracked up to be, depending on how you have to get it. so not really something to spend a lot of worry on to start with. 'Nuther one'a them basis for comparisons for later thingys. (There are a bunch of those, by the way.)
Same for feed lines, and radios. Just a matter of experinece and preference. They have favorites, you will have favorites and I have favorites. I seriously doubt if any of them are the same. (Naturally, mine are the best! They'll say the same thing, but what do they know.)
I can't think of anything you've brought up yet that can't be 'improved' on, or made 'better' in some way. But all of those 'some ways' are not all that critical, really. I am very willing to bet that whatever you start with, won't be what you will be using as soon as you have the chance to try something different. That's as normal as it gets with radio stuff, and almost anything else I can think of. There will also be some "I wish I hadn't done that" thingys!
That's normal too. Just remember the mistakes and don't do them too many times again.
Aiming for perfection is good! Achieving it is never gonna happen, something will always sound better later. That's what that 'basis for comparison' is all about.
Those are my "words of wisdom". I figure you'll use them about as much as I did when I first heard them. Oh well, so what. As that song says, "Faster Women, Younger Horses, Spend Money!". ... I think that's how it goes, ain't it?
- 'Doc
(Boil all that mess down and you got bigger, and higher antennas. Sort of.)
