Heroes!
Patch 1.1.2.1 adds an option within the in-game network settings: Quickplay Search Range
A change has been identified in the way Steamworks handles download region selection & matchmaking geolocation. We understand this is awaiting further tweaking & in the mean time we are implementing a toggle that allows you to opt to extend the in-game matchmaking to look further before starting self hosting.
This patch implements that option, which can be found in the Network Settings in-game.