What if I decided to go with the 1st choice among the three options, the water-based sorcerer, and named him Prospero Milan? Furthermore, what if I gave that character more servants to attend to him, spirits or djinns of elemental power and origin? What if I based these two on the same Shakespearean theme of The Tempest and named them Ariel and Caliban respectively?
Ariel - The most powerful water djinn that attends to Prospero faithfully and affectionately without question or shortage, she devotes her entire being to her master. As a water-based spirit, she has complete dominion over all of the lakes, rivers, ponds, oceans, and seas as well as the airy dominion, able to conjure storms, lighting, thunder, and other weather apparitions. She also has the power to change her form, to be invisible, intangible, change her size, duplicate, and even assume an elemental form (water). She often is the mentor, protector, and close-friend to Prospero, but silently wishes for her freedom to choose her life rather than his dictations. The vessel that she resigns is silver ring inlaid with a large, uncut-flawless sapphire which is crafted to be worn and only work for Prospero yet it requires an incantation to summon the spirit/djinn.
(Inspired by Miss Diamond Doll)
Caliban - A lesser fire djinn (ifrit) that was created by Prospero rather than obtained like Ariel in his earliest attempts at conjuration. It was not a complete success as he is proven to be weaker in many aspects compared to Ariel. What's more is that he has no love for Prospero, even goes far as plotting his demise secretly; actively seeking a new master to manipulate into giving the order to kill Prospero for example. Despite being a lesser djinn, he has great physical strength, endurance, and resilience towards most dangers and can call upon fire and earth. He lacks, however, the speed and agility as well as most of the abilities that djinns possesses such as a complete elemental form. For this indignation, he loathes Prospero for creating him as an inferior being. The vessel that he resigns is a solid-gold oil lamp (Moroccan) that can be easily summon by rubbing it, without the need of an incantation. It can, however, be used by anyone outside of Prospero's grasp.
(Inspired by Kazaam/Shaq)

Made by  pranky1