Jayce's Design is a Fantastic Role Model

Jayce is a great example of what Riot should strive to achieve with every champion.

Jayce can be both dominant and supportive in his kit while putting every part of said kit to use. Nothing in his kit is irrelevant except his mana regain during Melee W's duration (which is so barely noticeable that it doesn't matter). Jayce can effectively use his gate shot to poke targets to discourage advance or soften teams up for an aggressive engage. His gate speeds up teammates as well as gives anyone in it a means to quickly dodge skillshots. Jayce can leap and set up a pick or knock away the most dangerous target in an engage. Jayce can triple shot enemies to shred them or absolutely destroy a tower. Jayce can leap sighted walls onto targets or bash targets through them. He can deal monstrous damage with his simple shield presence and basic attacks. He is squishy as hell but rewards risk and calculation entirely.

Jayce has no easy escapes and it's very easy to catch up to him. His actions are easily punishable and his lack of defenses make him decide his battles or die every time he leaves base. Playing him isn't a breeze and he is not a character that makes easy plays with maximum reward. I feel he deserves more respect as opposed to who with minimal effort can chunk teams at a whim.

Jayce sits well next to due to the fluidity of mechanical control and power through decision. The only reason I don't praise Yasuo is that he is forgiving as a manaless champion whose CDR is so stupidly low that you could destroy a line of people with several mistakes in between.

would sit in this category as well but some of her moves could use tweaks in how fast they proc and how much damage they do. Taliyah is good in the right hands but she can't compete against the recent AP Rework champs in terms of how stupid they melt people. Her maneuverability (much like Yasuo) is something to be relished and really should get more respect in terms of how you weave through a battlefield.

TL;DR, Jayce is a perfect example of being a high rewarding champ without being so OP that anyone can use him. He's also a champion that feels like all of his aspects matter at every phase of the game. In addition to this his visuals are still awesome and his personality (despite how hero-generic it may be) works in his favor.