1) piety gain for JJ between Wizards and Paladins would be equal. Given that BURNDAYRAZ is not a spell that grants piety for JJ, and BYSSEPS and GETINDARE are
That's stretching things, especially since the wizard is more than capable of using these glyphs in a piety farming context. You don't actually need to
use the effects, just trigger them. In any case, the Paladin would need to be two levels of boost mana ahead of the wizard to have a discernable advantage, and this isn't going to add up to
that much piety.
Furthermore, this case is the most extreme in the Paladin's favour. If you add in other factors, consider other deities or combos, the Paladin really has no advantage over the wizard.
2) You regard monotheism in MA and EM as a curse - I disagree. In fact, quite often one of the last things I do before ending a level is an Entanglement; I've been known to convert out of other religions to pull that off
Yes, and Paladin does not have the option of doing so. He does not have the option of converting into Earthmother after leveraging another deity, nor converting out after grabbing the boons he wants from her. With plantation on the menu, piety literally grows on trees and the sky's the limit in terms of conversion antics.
It helps that EM is very hard to piss off, too.
This is not a point in the Paladin's favour, since being able to brazenly piss off his chosen deity is one of his core advantages. It's not worth a whole lot in the case of EM. He's basically just got the 20% discount on one hand and the inability to convert on the other. On a deity with such massive piety generation potential, I'd give up the discount in a heartbeat to convert.
I think you underestimate her (probably because her "punishment" is pathetic, making her an easy desecrate target.
I'm not saying EM is bad; I'm saying she works best with the option to convert. She's basically the only deity with the piety generation to grab everything on the menu and
still convert out with 100 piety. For a conversion-heavy approach, Earthmother is great. And yes, desecrating her once you're done with worship is yet another bonus.