whats more important for familiar? familiar type or blood %?

[BoromiR]

basic crossbowmen 95% or paladin 50%?

[Suzaku]

Depends on what you're using them for.

For PvP defense, you want high blood% to make them stronger, and to choose the NPC that is most difficult to fight since they keep their AI and attacks.

For PvE missions, you want high blood% for better success rates (though gear is what's really important), and a variety of blood types and factions for the bonuses those provide.
https://vrising.fandom.com/wiki/Servants?so=search