I would say that one of the big problems that new users face is content discovery. If you only follow one or a few npubs, your feed will be pretty sparse, and it can take considerable effort to find who to follow. This is where WoT can help: even with only one or a few follows, your GrapeRank content feed can be fleshed out immediately (ie feed = top N npubs based on GrapeRank score).

What other onboarding problems do you have in mind?