Li Shenron
Legend
I don't see a major problem with your proposal, though it might result in some analysis paralysis and some cherry-picking. If you trust your players and they're not staring at the infinity of spells slack-jawed and overwhelmed, it sounds solid.
Isnt' that the same with Sorcerers and Wizards tho? And they even have a longer list.
I think it depends on the player:
- One player may be paralize by having to cherry-picking, knowing that she'll be stuck with her choice until next level. The bright side is that after the choice is made, there is little to think about for a while.
- Another player may instead take ages when preparing spells, going through the whole list each time there's a long rest.
But I think the easiest solution is the solution that 5e has as a default: Don't add cleric spells. Add domains.
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I'd treat druid spells similarly - new or variant lands for the Circle of the Land. Paladins? New Oaths. Rangers? No mechanic exists at the moment to give rangers bonus spells, but I could see it as another subclass.
Like, if you wanted some of the spells from the Elemental Evil PG - sounds good. Lets make an "elemental" domain. Or an "earth" domain. Or whatever.
That's also an awesome idea, but I seriously doubt that WotC would do it. They'd just add new spells to the main Cleric list. At least we know it's not going to happen very often anyway.
BTW the Ranger already doesn't automatically know all spells on her list.