As someone whose job requires me to deal with a lot of end user confusion, I’m pretty passionate about UX, so please excuse my long winded reply.
I do think that sometimes a slightly inaccurate name (like Community Decks) is still better than an overly abstract one (like Community Centre). Doubly so in this case, since the Community Centre that most people already think of when they hear the term is a place to go and socialize within your local community.
You could still include things on the actual page to quickly call out that there are also templates and layouts available. A header that gives an expanded name like “Community Decks, Templates and Layouts” could work – perhaps even with a direct link to take you straight to that section, if it feels that important. You could even label the sidebar “Community Decks+” if the inaccuracy really gets to you.
But if 99% of the time, people go to the place looking for decks made by the community, I’d argue Community Decks is still the better name in practice.
If are set on the Community Centre name though, another idea could be to switch up your icons. The three dots for the Community Centre are juuuust close enough to “bubbles” to be associated with thought bubbles, which aren’t a far cry from speech bubbles, which also happen to be used for both The Den and for Knowledge Base. Worse still, the two speech bubbles for The Den have just enough overlap to make them a little difficult to make out as speech bubbles.
You could try switching the Knowledge Base to something without a speech bubbles at all, switch out The Den with something a little more clearly speech-bubbly, and pick something else entirely for Community Centre. Perhaps a third variation on the the Deck and Card Generation icons’ look, to give their overlapping primary purposes some visual overlap as well.
Anyway, this site rocks, and I’m super excited to have found it - I’ll be grateful it’s all here no matter what it’s called!