This is the method I use.
(Total sum of CRs*4)/(total sum of levels of PCs)=difficulty
<=0.25 trivial
<=0.5 very easy
<=0.75 easy
<=1 medium
<=1.25 hard
<=1.5 very hard
Higher: avoid if possible or alternate win condition
I think the issue is just a matter of CR calculation and counting action economy of enemies (XP multiplier) when players already have area spells and the like.
Levels 1 and 2 are brutal though, and I was scared of what a small group of goblins could do to the PCs.
But I would easily throw...
Plane Shift Zendikar and Plane Shift Ixalan have each one rules for (pseudo)Vampires (they can be in sunlight, etc.). So you could use them as they are or as a base for your race.
Zendikar has the savage ones and Ixalan the knightly ones.
Things we could expect from this.
1. Ordeals of the Gods (there are 15 gods in this setting, not counting Xenagos).
2. Satyrs, gorgons, minotaurs, leonins, merfolks.
3. A couple of thematic subclasses.
4. Realm of Nyx (gods and Nyxborn realm)
5. Underworld realm (returned, titans)
6. Greek...
Third session of Lost Mine of Phandelver.
My players got captured by the bad guys and imprisoned in their hideout at the previous session.
They managed to escape, although the mother and kids died falling into a pit. Then managed to surprise and kill the leader of the gang.
They ended up...