I imagine I forgot half the suggestions I wanted to make but this thing is already long enough.
As to quality of life:
-Abilities to check weather and current mob for blood without always heading to the ghoul. Can make it cost blood or some reagent.
-As an alternative or just addition to the above it could be a perfect time to add another 'Familiar Recall Collar' for Truxartis like from Cinnamon for animal town. You are his fledgling afterall.
-Some of the mob types for said blood are extremely hard to come by comparatively to others, elf being a prime example. Adding more spots for these types or doubling up types for daily blood would help a lot.
-A short immunity buff upon reviving when in Sunny areas and burning . Yes proper planning can almost always negate this from happening but It seems to be a problem for a lot of people.
-Some item that works like the Rage to heat potion for cold but instead for blood. Can be limited or tedious to acquire but it would give an option to playing in a bright area in case of need, group content or event content. Could also instead create an item that creates a zone for shadow or safety with a duration to alleviate this. Otherwise things like the Claudia world boss event ect are going to be abysmal based on weather and day/night luck.