Larger position indicator (arrow) when navigating?

Absolutely agree. It would be great to have a larger arrow with an ability to customize its color 

Absolutely agree with this as a trail runner in my 50s. The map readability is quite poor for my aging eyes, especially during winter when there is less light and the contrast is worse, and I often find myself not being able to see anything on the map. That is mainly because the sapphire screen contrast is so poor and many of the map elements are tiny and thin and don't always use contrasting colors. Even when I switch the map to High Contrast theme, that doesn't improve the map readability very much. For example, the background is often light green and the trails are dashed red lines. When there isn't enough light (e.g. in the deep forest during winter), there is so little contrast that I can barely see those trails.

I don't need all the tiny details on the map. I need to clearly see a few key elements, like trails, creeks, etc vs. my position. What makes is much worse is that the map orientation is quite laggy. I often get disoriented when I am coming to a trail intersection because it can take up to 10 seconds for the map to orient properly when I run on trails with a lot of turns. 

This is one reason I start to consider moving back to Suunto where map rendering is supposedly excellent. Suunto map was designed for athletes who do fast paced sports like trail running, unlike Garmin maps that seem to have been designed for hikers.

What we really need is a truly high contrast map theme, where all elements are bold and can be clearly visible even when running at full speed. We also need responsive magnetic compass and the map orientation responding quickly when direction is changed.

That's exactly the same thing that happens to me! Every time I use the maps I end up thinking about switching to Suunto (even though in some ways it is very very far from Garmin) just for the readability of the maps.
Maybe Garmin could come up with a "trail run" theme for maps with much less detail and much more focused on roads/trails and position.

I am having the same problems. I have switched to Epix pro but the problem is not solved. I had a very bad moment in a race when I thought that I have lost the trail. It was impossible to see on the watch if I was on the track or not (the race track was loaded into the watch). I could really use some readability improvments here because I find quite impossible to take my glasses with me and using them during races.