I predominantly use verticals on all bands above 40m.
The first thing to realise is that all antenna systems that are used for portable operation are going to be compromised in some way so try not to make your antenna too complicated. This suggests a resonant design for different bands; try to avoid lossy coils and traps.
In an ideal situation it would be nice to have 1/4 wave antennas with sloping radials but it is really not easy to do on bands below 20m with short poles.
As an example I use a full 1/4 wave antenna on 40 metres with the radiator 9.5 metres long and wrapped around a 10 metre fibreglass fishing pole. There is no way of having elevated radials so I just run three resonant radials from the base at ground level. Does it work...? Just look at my activator logs.
40 metre vertical on Pen-y-Ghent; the radials have just been thrown across the snow!
On holiday the two main bands I tend to use are 20 and 17 metres, again vertical but with links to change bands. This time I use a 5m travel pole (1/4 wave at 20 metres) with resonant radials along the ground.
20/17 metre vertical in Lanzarote; you can just see two of the red radials on the ground. Some rocks were used to restrain the guy-lines
In both cases the antennas show a good match to 50 ohm regardless of the terrain the antenna is used over. This is essential for me because one of my amplifiers will fail if the VSWR is too high.
The easiest way to hold it up is to use three guy-lines pegged with tent pegs or tied to anything suitable at the location.
So decide on the bands you want to use, choose the pole you want to carry and go and cut some wire and experiment.