Something occurred to me about the difference between "Permanent Devotion" and "Spent Devotion" ... PD lends itself to story arc - a change in scope
from the early game to the late game. This is the kind of thing I think
can give a game an epic feel. SD is more cyclical and therefore
tactical - once you spend your devotion, you're back to the beginning, and in the late game you're doing the same kind of things you were doing in the early game.
There could be "city" type spaces indicated on the board, where you would want to move your units. Maybe these cities are worth points to the player with the most units at them (at the end of the game for example), so part of the game is "fighting" over cities via area control (and perhaps there are ways to remove pieces from the board - actual fighting). I think I'd want the actual directly interactive fighting to be minimal/secondary in this game, because I generally don't like those types of games.
Athena - monuments
As always, I welcome your thoughts on this!