I have a seemingly simple map - around 150 points with lat and lon, spanning a few countries in South America. So I'm surprised to find it consistently takes 10-15 seconds to load. All the other visuals on the page (including a table with the same rows) load in 1-2 seconds. After the map apparently has loaded, the "spinner" (animated bars at bottom left) keep moving, seemingly forever.
I duplicated the page and changed to a "Bing" Map visual - it loads in 1-2 seconds.
Once loaded the ArcGIS Map is reasonably responsive, e.g. zooming or filtering.