Default color palette and Blending mode to multiply

[SanttuVP]

Expected behaviour
It could be beneficial for the user to see the results with default styling regarding also the use of color palette and the Blending mode. Although it is not necessary for the plugin to guide too much the user in their visualization decisions, it could be helpful for them to do something as follows per default:

Visualized with the basic OpenStreetMap basemap.

Visualized on top of the Toner-basemap from MapTiler.

Visualized on top of the Satellite-basemap from MapTiler.

In addition to the points mentioned in this Feature request, this was achieved by using:

1. Multiply as Blending mode
2. Colorblind safe color ramp from a darker color to a color that would blend more effectively with the background

Current behaviour

Visualized on top the basic OpenStreetMap basemap.

Additional context

• This Feature request does not assume that there are any "right" choices for visualizing these types of geometries, instead, the point is just to help the user to get started with the styling.
• Partly, in addition to a feature request, these are notes just to give context for the wider usage of this plugin.

This Feature request is related to the following other feature requests:

• Isochrone-geometries ordered by the isochrone_distance-column #30
• Default styling configurations for the output isochrones #31