I'll start by saying the resources and tools you mentioned overall in your post are fantastic, and your approach for LR activity is also great. At the same time, I will acknowledge that from personal experience this is one of the least effective methods for actually getting a member to do something new, or to teach someone something new.
I have rarely had success with team pings to get prospects or non-max earners to do a task or claim things. I find that the only time I have success is with one on one interaction and outreach by me. I'm not trying to flame your approach or say you're doing it all wrong since the LR component is great for retention. I just think that the approach for development could be tweaked. Plenty of newbies will just mute the team server or role pings and never see them again. DM's can be blocked as well, sure, but I've found that reaching out directly and bringing a personal approach is a lot more effective. We can't always expect new players to self serve and be independent even if we centralize resources, they still need guidance with a personal touch - that's what GM's are for.