The error was that SDV Expanded was missing a dependency, and wasn't loading.
Because, it wasn't loading; the custom NPCs caused a crash:
Code:
[19:46:35 TRACE SMAPI] Stardew Valley Expanded (from Mods\Stardew Valley Expanded\[CP] Stardew Valley Expanded) [content pack]...
[19:46:35 TRACE SMAPI] Failed: it requires mods which aren't installed (aedenthorn.ExtraMapLayers).
...
19:50:52 ERROR game SContentLoadException: Error loading "Characters/GuntherSilvian": it isn't in the Content folder and no mod provided