It's clear that it should be "better" to have the PL.
I think cross-class comparisons are useful, especially since we've got a matrix (past life, if any ... current life, etc.). Does this make a fighter PL as useful for a melee as a wizard PL is for any caster?
This isn't a "balance" question with only two individual factors; the game is far more complex than that.
(EDIT and just so I'm clear - you're only talking about the framing of the comparison; there's no implied opinion on your part that it is or isn't OMFG-broken?)