People have actually been asking for a solo version of Aztel's Fortress for years. That made quite a few people really happy.
I myself have no problem with re-using some assets like that. It is better than getting nothing at all. You have to remember indoor zones like that take far more time to create than a larger outdoor zone.
By definition, recycled content is not all new everything. Good thing they gave us some content that wasn't recycled too. There is no problem with having you re-visit some old areas with different quests and mobs.
You have a quite a few glaring inaccuracies in your post. Funny that you say "No one would want to do this outside of leveling up", since that is exactly what lots of people are doing. Or that Bear mounts don't jump, when they clearly do.
As to your mention of taking 6 months, that is not true. It should be do-able to get full faction in less than 1 month if you do it every day. That isn't to say it doesn't take too long. I would like it if the mobs all gave faction too.
Please try to be accurate in your posts instead of spreading misinformation.
I also hear there is a new continue feature for going back inside after zoning out. Not sure how that works, but it sounds like Funcom is addressing some of the biggest problems with the new content.