Hey Ian,
Long time no see eh?
I think you can easily do what you want without any major complicated work. Using the Sitemap, you can already mount two versions of the same ticket tracker because all of the tables contain a package_id, thus if you have two different urls set up for your ticket tracker, you will see them as two separate ticket trackers.
In the ticket-add page, you could have a person choose which workflow they want to use, and modify the ticket-tracker.new proc to accept this rather than the hardcoded one. An alternative method of choosing which workflow to use, you could use ad_conn url, find out which url you have come from, and select the workflow based on this.
Hope this helps!
K.
