Biggest Fails for me are:
Conversations are hard to track (
http://xenforo.com/community/threads/conversations.15900/ ) and the conversations overview is horrible.(no way to delete selected conversations, no way to see all participants,...)
Nodes:
It's a smart system, but it's not
thought out properly. (e.g.
http://xenforo.com/community/threads/search-form.14759/ and several other suggestion, don't want to search and link all
biggest fail=> ALL nodes are returned on places, where only forums (or an other type should be shown..)
The node permission system is IMO also really horrible to manage, once you've installed several add-ons, because you'll get ALL permission groups for the current node (i wish there would be a filter to show only the necessary permission groups.. suggestion was made already....)
"What's new" isn't global. It's returning only new posts and not all content types...4
Sidebar is nice, BUT it would be much better, if we could have the sidebar on EVERY page.
Also a sidebar block manager with ex/import feature would be great.
ATM we have the [bd] widget framework and sidebar block manager included in my add-on helper framework, but it would be much better to have 1 easy to extend interface to manage them...
Template Hooks:
They are nice, BUT it's horrible to wait for them as developer...
why not have a automatic system? Todays standard is a automatic template changer....
Last but not least because it's causing me the biggest headache:
http://xenforo.com/community/threads/event-listeners-to-manipulate-criteria-in-controllers.18072/