Its crazy! Tons of my companions are dying and their levels are much higher then the mobs. I know I am complaining too much about Valencia but this is just insane.
yep Granchia can be a lot annoying, the best tip i could suggest you is:
for the side quest of collecting art pieces just move between the 2 guys at Granchia entrance, there is a jar and a chair spawning relatively fast and without mobs around; for cathacombs instead just go and try to do only one fight on your travel, then when you defeated them meantime you are in invulnerable time (the semitransparent effect), run to the entrance of cathacombs . At all you would need just one fight in Granchia.