A good question. The statistics to calculate the fire resistance title are saved, but the title itself is not currently in the game (it was just cut because I was sick and tired of developing dungeons and wanted to boot that out the door even 10 seconds faster...). At this point, adding fire resistance isnt something that would take more than a few hours, so I'll pencil that into the schedule for the upcoming version. Honestly, I had forgotten all about it, so I appreciate the reminder.
Things like the blood stones and shadow stones are certainly planned to be future consumables for special-type magics (more skills will unlock as you use them, requiring more stones in turn). The issue on this one is really just a question of priority: do I spend my dev time expanding combat and dynamic content like additional dungeon types/explore locations, or do I spend it on story content? I'm trying to do small increments on both, but it sort of leaves every aspect of the game feeling unfinished, right? Questions and comments like these are largely what I use to help decide the priority on smaller game additions (smaller being new titles or quality of life changes, vs larger updates, like adding status effects to cooking).