With the current color for a GPS track, I have difficulty distinguishing between a GPS track and the roads on the map I use. With for instance the map source OpenStreetBrowser the orange color "colides" with the main roads color. My guess is that a perfect color isn't possible, so you probably want to have a setting for picking the best color for a certain map source.
Currently the location arrow is red and, on an ipad, not all that big. Since I'm using various map sources, sometimes the red arrow cannot be distinguished from the background color - for example when driving on a highway colored in red.
I'd love to be able to change the color and size of the arrow to make it stand out. Perhaps even have other visibility aids, like somekind of translucent halo around the arrow.