I am currently developing this, with a lot of help from @Chris Deeming, who has to be commended as I know absolutely nothing about php so it's like explaining rocket science to an illiterate farmer, sorry Chris
Essentially it will allow anyone with the relevant permission to feature/edit/unfeature any thread, which will be shown on the forum index.
A maximum number of threads can be configured and each page load will randomly select one of those threads.
When a new thread is featured, the oldest thread will be dropped.
When a thread is being featured (or edited), the title and content can be edited, to allow for some editorial control.
Only those with the permission to view threads which have been featured will see them (global and per-node).
So if threads from a private forum are featured, only members with access to that forum will see them.
If threads are deleted or moderated, they will be removed from the featured thread list.
I plan to strip out bbcode, attachments and smilies and just have plain text as I think that works best for what is a fairly small snippet of a thread.
Although URLs will be preserved.
So far I have done the permissions, style properties and options.
The permissions also cater for individual nodes.
The templates and styling are done:
This is how it looks with all the Style Property options unchecked:
Or with just the avatar and "Read More..." link
It's fully responsive - the avatar disappears in the narrow view for example.
And for those of you who like to get your money's worth out of your widescreen monitors, it also works there too:
It's still early days and there is a lot to do but I have made a start.
The php is very basic at the moment and it will be slow going due to a) me not having a clue and b) only having around an hour or so each day due to real life commitments.
Hopefully it will eventually see the light of day.
Edit: I should add that this is all part of my idea to have a combined portal and forum page - I'm not entirely sure how that's going to look but in my experience people don't use portal pages, they usually skip them and go straight to the forum, so this is some way of trying to address that.