Takes a location with a nexus that's in ambit, stores that location to your player data, that location no longer needs to be in ambit to bind to it.

Might I suggest that this be implemented similarly to how HexBound's Memorize Pigment spell works? With that, you associate a pigment (don't remember if it's your current one, or one grabbed from an item) with a pattern, and later you can use Recall Pigment with a pattern as input to set your pigment to the corresponding one.
So you'd have the memorize nexus spell, and then modify the bind and temp bind spells to optionally accept a pattern iota instead of a vector.
This way you could connect to the memorized nexi from other dimensions.