Glad to hear the mtn running bug bit you – wide worlds open up when you realize how much terrain you can cover when running!
I’ve used both the Leopard FL and Kahtoola Microspikes for trail shoes while moving over snowy terrain. Short of really steep and really firm conditions, I’ve found the microspikes cover most bases quite well and their lower profile is easier to move in, whereas the Leopards as a more conventional crampon can be a bit ungainly when you’re moving between steep and gradual grades.
For something like the Ptarmigan where most of your snow/glacier time is in traverses and rarely steep and straight up, I think the microspikes would be great.
Not sure if you’ve seen, but one of our coached athletes, Mike Foote, and his partner Stephen Gnam ran the Ptarmigan last July and didn’t bring crampons or spikes, based on an earlier scouting mission: https://uphillathlete.com/ptarmigan-traverse-fkt-mike-foote-running/.