| When you sub a job, you get certain abilities from that job, you're not exactly a hybrid. What I mean is a BLM/MNK can't cast magic and hit with grapples, or a WHM/WAR can't whack a monster with a huge 2H sword.
Your main job defines what you are, your sub is to grant you abilities to help that main. MNK in this case will do nothing for you but give you HP, which is useless. You can't wear grapples because BLM's can't equip them... what you can use is dependant on your main job.
So... you sort of implied, yes it's prudent you be a BLM/WHM if you want party invites. You can nuke, as well as be invited to be a backup healer. Any mage that can heal is very useful... I don't think you'll be called often to nuke unless you're fighting something weak against certain spell/types.
If you want to be a mage that can also swing a sword and be semi-useful with it RDM is for you. They can solo monsters by using their black magic and white magic, plus their sword attacks. When you sub /WAR you can use 1H WS... thats pretty intriguing. You'll eventually end up being RDM/BLM or RDM/WHM and not even get close to the monsters when you're in PTs, but atleast in your early life you can even tank!
Sorry man, in this game it's all about maximizing your usefulness... if you're a mage that can't heal in emergencies and can only nuke you're pretty much useless. Not to mention mage subs grant you a LOT more MP... so it's useful since you get lots to spare on heals in between nukes.  FFXI |