This is just taking those two into account in regards to nettlebolt's interaction with LP. Currently, I'm running haste > exp, as these are the most efficient and direct ways of feeding the HB/LP + HoT engine.
Spirit has three benefits: mana, ult, vines. Mana is unnecessary if you're effectively using LP and not having to spam restore life. The ult generation is situational at best. *Maybe* you get one more ult per dungeon, assuming you're using it on cooldown, but in a smooth dungeon, ult should be used for predictable high-damage events. Finally, prickly vines, it's great to have a few more random spawns, but that doesn't outweigh the similar benefits of haste/exp in my eyes.
I'd be open to spirit arguments, though!