Let's Give Quinn some quality of life buff as well
While I know that Quinn isn't the most in need of a quality of life buff, I noticed there are some areas of her kit that could really use a little mercy for games where she's not doing her best.
1. Let her Q, Blinding Assault, trigger the Vulnerable passive If her passive is going to trigger on people farther away from her auto attack range and she knows that it would be havoc for her if she tries to AA that target, let her trigger that mark with a single Q. It provides game play strategy as well as utility. Does she use the Q to provide that extra damage onto a far away target or does she keep the Q in case the enemy bruiser tries to jump onto her face? Like Riot said in Quinn's reveal and spotlight, "Blinding Assault is Quinn's only form of harass, so use it wisely". And what a interesting mechanic it would be to create that sort of situation in a game.
2. Let the Vulnerable passive be more forgiving with targeting low level minions One thing I noticed when farming, or just in general, Vulnerable will occasionally target a minion that has literally 6 hp left and has 20 minions attacking it. There's always a delay between when Valor will target the next enemy with Vulnerable and nothing is more aggravating than a vulnerable buff like that simply escape your clutches because you didn't AA it in the .01 second time frame you're given. My suggestion would be, the vulnerable mark will disappear after a certain time frame or if the enemy strays too far away. If the target marked with vulnerable dies without being detonated, it will instantly mark the next nearest target. This is only a suggestion, I don't know how well it would work out in play testing. I just would like a little more mercy with the passive targeting system.
EDIT: The Vault idea was interesting, but didn't fit her kit well. Perhaps it would be best suited to be conferenced about in the Champion Concepts boards. I took the paragraph out, and edited some parts of paragraph to emphasize the first two points.
TL;DR, Let Blinding Assault trigger Quinn's passive, make Vulnerable be more forgiving with its targeting.