Symbol improvements in trip visualizations especially with bigger symbols

**Is your feature request related to a problem? Please describe.**
I would like to be able to render symbols in trip visualizations as points, rather than ermm.. strokes(?). Currently the only available symbol in trip visualizations is a stroke, that looks really strange when the symbol size is increased beyond a certain threshold.

**Describe the solution you'd like**
I would like to see other symbols (e.g. simple points) as an option to the current symbol

_Edit: also it would be nice to set the symbol size and trail length based on an attribute value_

**Describe alternatives you've considered**
In addition to points, there could be a selection of different symbols (e.g. arrow)

**Additional context**
Here's what I'm getting now when I increase the symbol size:

Here's more what I'd like to see: