Hehe, youve got the best euro class

hehe.
IMO a cleric doesnt need any sub-class, just be only cleric, because un lvl 10 you will give nice buffs (extra str/extra int), and if you change to a subclass, the buffs will over, and is annoying to buff again, means waste of MP.
SP farming is that action which you kills mobs for get more SP with some conditions.
If you will be an full cleric without subclass, YOU WONT NEED TO FARM, u will have enogh SP for learn all the cleric skills, which are so useful.
Keep the cleric, will find party easily.
Byes and luck