Jarvan IV: Thoughts and Discussion
There are things about Jarvan, like his Cataclysm (ultimate), which is obviously really unique, but is outdated with all the mobility added to the game. So it may be better to update and shift power from this all at the same time, like remove its damage and re-distribute it into his base kit and have the ultimate prevent enemies from escaping by any means [similar to Camille ult] that are inside of the ultimate, still impassable terrain for all units as well - this should allow for an easier time to adjust the duration between patches since its power is consistent against everyone.
Other things will be Passive, Shield, and Flag are all outdated abilities as well; only thing still cool and unique is the Flag+Q combo to knock up enemies, but all of these abilities can use some work. Maybe even take away power from his Q even and redistribute to more updated abilities making P-W-E more exciting to use; passive specifically is outdated being the fact that it is a weaker blade passive most of the game until its final rank and then also has a long cooldown with it.
~ In short, update his ultimate to be consistent against every enemy champion and take away power from his most powerful abilities [QR] to make his lackluster kit better to use (just adding power would make him overpowered, but redistributing power keeps his power levels the same with a more exciting base kit).
Base Attack Speed: 0.677 +3.5% per level [from 0.658 +2.5% per level; no more bonus attack speed in his kit, so more base attack speed to help him jungle]
Martial Cadence (Passive): Cooldown: 8 seconds [lowers with CDR]; Radius: 350 units Jarvan IV's next basic attack slows nearby enemies down by 20/30/40/50/60/70% for 2 seconds and deals 5/6/7/8/9/10%(+4% per 100AP) of targets' maximum health as bonus physical damage (max 300 vs monsters).
Refunds 50% of the cooldown if Martial Cadence damages at least one monster.
[RANKS AT LEVELS 1/4/7/10/13/16]
Dragon Strike (Q): Cooldown: 10/9/8/7/6 seconds; Cost: 35/40/45/50/55 mana; Range: 750 units Jarvan IV extends his lance in the target direction dealing 10/40/70/100/130(+100%AD) physical damage and reducing armour by 10/12.5/15/17.5/20% for 3 seconds, this can stack additionally with Dragon Might.
If Dragon Strike collides with Demacian Standard then it pulls him into the flag's location knocking up enemies along the way for 1 second.
Dragon Might (W): Cooldown: 10/9/8/7/6 seconds; Cost: 35/40/45/50/55 mana; Range: 750 units Jarvan IV extends his lance in the target direction dealing 10/40/70/100/130(+100%AD) physical damage and reducing armour by 10/12.5/15/17.5/20% for 3 seconds, this can stack additionally with Dragon Strike.
If Dragon Might collides with Demacian Standard then it pushes him away from the flag's location shoving enemies he makes contact with him along the way.
Demacian Standard (E): Cooldown: 14/13/12/11/10 seconds; Cost: 50/55//60/65/70 mana; Range: 800 / 600 units Jarvan IV throws down a flag at the target location granting a large amount of vision around it and remaining in play for 8 seconds.
If an allied champion or Jarvan IV collides with this flag then it shields all nearby allies for 60/80/100/120/140(+40%AP) shield for 4 seconds plus an additional 2/2.5/3/3.5/4% of Jarvan IV's maximum health as shield for every enemy champion that is near the flag.
Cataclysm (R): Cooldown: 120/105/90 seconds; Cost: 100 mana; Range: 600 / 350 units Jarvan IV does an unstoppable leap to a target enemy champion creating a ring of impassable terrain for the next 2/2.75/3.5 seconds and causing all enemies within the arena to be unable to leave by any means. Jarvan IV gains 0%, 15%, 30%, 45%, or 60% damage reduction depending on how many enemy champions are trapped in the arena.
Jarvan IV can cast Cataclysm again to end the effect early.
(So your passive is now a one time AoE attack that slows enemies and deals bonus damage, being treated more like it is a 5th ability rather than something is just there and is based used AFTER the entire combo to go J4's armour shreds [Q is less shred but now stacks with essentially two Qs with QW for slightly more shred than before] to give his kit better synergy and it be AoE really focuses on landing a 5 man ultimate so everyone is damaged from the passive shot.)
(Q+W when on their own are the same ability, but are completely different when paired with the flag, with Q being the same as it is now where it drags J4 to the flag and knocks up enemies along the way; W is a lot different where it PUSHES J4 away from the flag and enemies he collides with are also pushed so you can knock up enemies and then push them together and then use your ultimate combo'd with your team - especially if you build a death ball comp around J4. The damage is changed to better go with a tank build from 120% BONUS AD to 100% TOTAL AD, so scales slightly worse for building damage, but is better when go for a mix of damage and tank [especially tank since J4 is a long range initiating tank that wants to set up his team to win the fight].)
(Finally Demacian Standard I want to stay as a team ability since it makes sense that way of waving the flag to motivate your teammates and make them strong to win the battle! The problem it has had before was that it was just a stat stick to your team that is hard to notice it doing anything meaningful and was really there to give J4 free assists [playing for the KDA yo!]. So now it grants a shield [one time per flag] to allies near the flag scaling mostly with J4 max health as long as the flag is also near enemy champions just like how his shield works now, except it is based on the flag's location instead of J4's. So he will naturally get shield when he E+Q combos to go in, but now he has the option to use the flag on an ally to try to save them creating more dynamic usages rather than always... flag=go ham, even if this is the case most of the time, the flag damage being removed makes better sense that the flag either shield be used behind the enemy for the knock-up or on an ally for the shield. Again, you are guaranteed the shield when you go in for the knock-up, but you can place it on yourself now and then push away from the flag with your new W as well - so more dynamic options to use the flag makes it innately more interesting to use.)