Good topic Ranger! I am working on this one right now as well.
You can make a relatively simple, light antenna that will do 80, 40 & 20, but not at the same time. By using a modified version of
this antenna (the first two pics), and a hand winder you can deploy it fairly quick in hilly terrain or with a few trees at just over head high level. I made up four plastic spreaders like in the pic and used an analyser to set points on
electric fence wire for different frequencies. Unroll the dipole to the frequency, pull the antenna tight and you are on. Made the 80 meter net all over the North Island and half the South Island on 20 watts with this. You need to get the frequency rolled out just right for it to work without a coupler and it is a very narrow band width so you will need to adjust the antenna if you want to move far on the frequency. I am going to make a few more mods to this antenna including making the ladder line section from insulated wire. I also use less wire resulting in a shorter ladder line since this is an expedient antenna that will not be up high.
That is why you should get a matching unit. For a manpack rig I started out with
this blokes design but replaced the antenna tuner with an SGC 211 coupler. It is lighter, smaller and will match a huge range of loads for five years from the inboard AA bateries. It also allows frequency mobility fast enough for ale use once the coupler has a match on each band. The SGC will also tune a 8 foot whip. I am purchasing an AT 271A folding whip and with a 43' drag line is supposed to give a decent signal on 80. I will let you know when I try it.