You do know that you don't need to increase the level back to maximum for all of them anyway right? I mean, the only one I keep the level up is the Missile Launcher and the Bubbler in the Final Cave. Besides, they're all going back to one anyway.
Kazuma and the Sky Dragon being gone...that's OK I suppose.
Is this because some dark wind goes through you or is it because of you getting hurt so much? If it's the former, you're taking the right route.