And I don't think a difficulty spike is going to address this.
I think the decision to move spells and abilities to be entirely per encounter has doomed this aspect of the game. Added to this is the removal of long-term health, the focus purely on wounds and removal of limited camping supplies.
These changes together have led to two big problems.
The first is that bite-sized encounters no longer matter. They are just wasting the player's time. Any fight that does not threaten to knock one of my characters out is meaningless. Because these fights no longer drain meaningful resources from the player, they no longer have any long term effect. And for players who take any effort to study the game's systems, the overwhelming majority of encounters in the game are going to fall into this category.
Think back to PoE1 with the temple below the first village, Gilded Vale. It was one of the first difficult areas many players would encounter, and yet no single fight in that temple is a maximum effort "boss fight". This kind of dungeon crawl cannot exist in Deadfire.
Upping the difficulty isn't going to change this, it's actually only going to make even more of a chore. All it means is that I go from using almost none of my abilities in these kinds of fights to having to use more and more of them. So long as my characters aren't getting knocked out, I don't have to worry about optimizing my performance in the majority of fights.
The second problem is that, even when the game throws a tough fight at you, requiring you to burn per rest items, empowers and suffer wounds, the cost of resting afterwards is so minimal that it's a no-brainer. Food is cheap. Camping is unlimited and risk free. The only kind of "agony" a player might feel in whether to rest or not rest is perhaps if they will burn nice inn bonuses or previous food bonuses.
It's a shame because I greatly appreciate the other aspects of the game such as expanded factions, better companion interaction, better thieving options and on and on. But combat, which is a core focus of the game, feels like a repetitive grind for all but the absolutely hardest of fights.