Just a general tip for the low level, mid-30s ASTs, about a problem I keep encountering from ASTs while leveling BLM:
At level ~35, no, my BLM does not want Spear right after using Raging Strikes. Spear would probably be better given to anyone else but me at that point. Give it to yourself during bosses for the MP/faster Luminiferous Aether, or the tank for CDs.
Spear tends to be pretty difficult to use in general and to do so effectively you need to know what jobs have which abilities, and how long their timers are. A lot of the time, in DF, it's probably best to just burn it for RR.
Amplifying this problem, a class that may not need Spear at a certain level range may find it much more useful at a later one, which essentially changes your Card strategy.