Official Hardcore Playlist(s)
Adding HC as a filter to existing custom search matchmaking would solve a lot of issues for the people seeking that experience. I don't want to cast aspersion on Portal - It's functionally a beta stack. The skill and capabilities of Portal creators are only as mature as the tools themselves. Just the way it is and will presumably get better with time.
I've seen discussion here and on steam concerning XP on Portal servers. As someone who isn't exclusively interested in most of the Portal experiences hosted right now or finding new, strange ways to get XP: It's easier for me to imagine an additional playlist toggle that adds an HC tag to existing and future game modes. (Honestly, even if it's only Conquest, most people would be happy).
People love it, it rarely affects balancing changes on weapons (there are some gadgets that become effectively useless though), and it doesn't become buried in a menu that is like solving a puzzle in order to find and lo, that the one server that got close to replicating the game mode is either offline or merely looking to seed players.
No-brainer.
Thanks for coming to my TEDTalk.
*Attached UI sample image since the in-line image is compressed to hell.