Lots of advancements in WSN's mapping functionality lately, as of 10.1.11 Beta 4.

First, the issue of not having all possible pins on the category or search map at once is at last solved. By setting Admin -> Settings -> General -> Map Pins Loading Strategy to "all", WSN will progressively load all applicable pins that are within the current viewport -- and when the viewport changes by drag/zoom, it loads anything needed for the new viewport. It's generally a quick process but there's a loading indicator bar to make it clear when it completes.

Second, I set about making it possible to dynamically filter the map by listing type by checking or unchecking a checkbox for each type. To use this, simply insert {FUNC_ADDFILTERPINSHTML} where you want the checkboxes displayed.

Third, in conjunction with the above I thought it'd be nice to visually distinguish pins of each listing type in different colors. This is now possible by setting the coloredpins tweak. Up to 7 colors are automatically assigned, and a colored pin is displayed by the checkbox to act as a visual key.