Upgrade LuBu after Dominating ?

Hey guys,
I have a hard time to get upgrades for LuBu, because now I dominated every Apostle, the last not-full-upgraded warriors are not all dying anymore with exploration... so I have a lack of Prestige points when I pay respects.

Is there a tip to get faster Prestige after Domination for upgrading last warriors which are not fully upgraded yet? Like removing all equipment to snail to be weaker and by this way, fight more rounds with random encounters ( = more chance to let warriors die )

Of course I could just explore again and again and I would get enough points, just wanna know if there is a clever way