Would it be possible to add a config to disable spawning with the baubles when first making/ joining a world?

I feel like some of the effects are a little powerful to have within seconds of starting a world.

Those options already exist. You just need to disable both Ring of the Seven Curses and Enigmatic Amulet (or whichever one you feel more concerned about) in Accessibility Config category within enigmaticlegacy-common.omniconf file. There currently are no other way of obtaining those items.