Arfur
A nice idea but most players just make an alt to go back to Silan.
That doesn't give you the achievements on your main.
The Kirosta boss is not so hard since it's always easy to find a high level player on Silan to help with it, and people usually do. Usually there is someone hanging around it farming it anyway, so many people don't actually experience that boss being a challenge.
The boosted end game version could be made hard enough to require a team of masters to take down so it would always be a challenge like the NPC bosses we have now.