I just realized something so obvious. TraversalSource should be fluent and not this awkward TraversalSource.Builder model we use. You should be able to do this:
Thus, TraversalSource methods return a TraversalSource.
That g is then "locked" with those parameterizations and any V()/addV()/etc. off of it will spawn traversal with that parameterization.
This would be backwards compatible. Though, deprecation would occur.
Finally, DSLs are still respected.
A fleeting thought...
So much cleaner than all that Builder-crap....