Ventus will always going to make it to the list no matter what despite her being an Elemental because it is simply necessary and I just can't help it but include our baby Ventus!
We're already in 4th jobs era and Ventus is still our best friend and our close confidant for everywhere else we go~ Whether we need to have Guyak she'll give it to us for free with the help of her Wind Step skill. Now you can casually farm Eden Coin (25223) at Second Power Plant and when you don't want to be late for events she'll make your move faster than the speed of light!
Baby Ventus with her Adolescent and Adult Forms can also provide easy access to 1 second FCT reduction when Lvl. 1 Elemental Control (Passive Mode) is activated which helps newbies early on in their journey.
Just be wary because once you use Ventus or any of the Sorcerer Elementals you won't be able to use or autocast your 4th skill Elemental Buster since this skill requires you to have your High Elementals present to activate.
Lil' Ms. Aqua is sometimes used in PvP scenarios like WoE and Battlegrounds (BG) where she's sought after because of her ability to increase Diamond Dust's crystallization's chance of effect by (JobLv ÷ 5)%.
Everybody knows how annoying the crystallization debuff can be when it's applied. You will be rendered susceptible to a couple of attacks, increasing the damage you take by 50% from Wind property magical attacks and several weapon types such as Maces, Axes, and Two-Handed Axes; not to mention you cannot move, attack, and use most of your skills and items. Truly, Aqua may look cute and innocent on the outside but she is as deadly as a viper!
Elemental Control (Passive Mode) is activated which helps newbies early on in their journey.
Diamond Dust's crystallization's chance of effect by (JobLv ÷ 5)%.