Would you say in this case I may be better with the wire coming straight down the pole?
That depends what you are trying to accomplish.
The 10m straight wire should work well on 40m without any matching. On 20m it will be a
high impedance: it can work well, but the SWR will be high on the coax which will increase
losses significantly. SWR will also be high on 80m.
The common 43' vertical and similar designs intentionally choose a non-resonant length to
avoid the high impedance of a half wave radiator. For example, 9m might be a better length
for 14 MHz (and 28 MHz) than a 10m wire without losing much performance on 7 MHz, though
both will be rather short for 3.5 MHz.
Another solution would be to run two wires up the mast - a straight one for 40m, and a second
with a trap or loading coil in the center designed for resonance on both 20m and 80m. That would
give you a low SWR on all three bands.
As others have mentioned, helical antenna design is not just a matter of winding some wire on
a former, and the resonant frequency isn't determined by a convenient formula based on the
total wire length as some might like. The Hamwaves inductance calculator (linked to earlier) is
probably the best way to check a design, but it assumes a constant winding pitch. Helicals with
significant shortening are often inefficient other than on their design frequency, though I've seen
designs that use a tapered winding (close wound for the top 1/3 of the antenna, with spacing
increasing towards the base) which was supposed to give better multi-band performance. Even
that was based on a specific wire gauge and former diameter, and can't necessarily be generalized
without further experimentation.