How do I get rid of "1 more subforum"? I want them all to be listed.
use this plugin.
http://mods.mybb.com/view/mytabs
by making the tab you can choose which forum can be displayed in the index.
and for a forum that is not shown you can access the link directly
Admin CP > Configurations > Forum Home Options > Subforums to show on Index listing > and enter some huge number (how much do you want)
If you want to display your subforums as columns it's just a template edit. No plugin required.