Don't know anything about Classic... but I can answer one:
[]- and the main one: TINY, TINY box/area to write the post (post message screen). Threads only has 5 lines whereas UBBC has 12 (I bet this is a really simple template alteration).
Thats a user setting.
Under "My Home", edit the "TextArea Columns" field and "textAreaRows" field. Users can make this box as big as they'd like.
As the Admin, you can edit the Theme settings. This won't override people's existing settings, but will apply to new users and users who aren't logged in.
Not sure how the import works... but you might wish to set this theme, then import the users, as I'm guessing the default will be applied.
A "FAQ - Site Help" post on display preferences and step by step to "My Home" are things that I am updating on my site, soon to be posted here for all to use in their own site. I'm guessing a forum like that, on your board would help the transition from Classic to Threads.
We don't have the forum here yet, but Maybe I'll post what I've got as a preview somewhere here.
