(Out of curiosity, is there any particular reason you want to use Twitter auth on this install?)

Since Twitter Plugin is "ready" and working, I see no particular reason to not enable it for this install :-)
I use twitter as my default login provider, usually. So it would be supportive to be capable to make use of it here for me, too.
Also, having it working in this install would raise the notification level when it is broken due to changes at twitter or such.

In theory, we should also configure these providers:

• Bitbucket
• Twitch
• Wordpress
• Phabricator (from admin.phacility.com)

Since this is both, Phabricator's project management tool and some kind of a demo of the product, enabling (/show off) as much features as possible isn't the badest idea.