Top 10 Things Kirito From Sword Art Online and Oliver Queen From Arrow Have In Common

In SAO, Kirito lost his guild when they were exploring an area, blaming himself for their deaths.
In Arrow, Oliver lost his best friend Tommy, his parents, Laurel, and friends from his 5 years away from Starling City.

Kirito was haunted by his flashbacks of killing so many Laughing Coffin members, shocking and terrifying him.
Oliver killed Count Vertigo when he was gonna drug Felicity, regretting it.

Both seem to have so much guilt over killing so many people and they were haunting them.

Asuna and Felicity are amazing!

Kirito plays many jokes on his friends, which doesn't end well for him.
Oliver does many idiotic things such as getting shot, injured, or anything stupid out in the field.

Kirito has Silica, Leafa, Sinon, Klein, Agil, Asuna, Yui, etc when he's out in the field
Oliver has Felicity, Diggle, Rene, Curtis, Dinah, Quinten,
In crossovers: Barry and Team Flash, Kara and Team Supergirl, Sara and the Legends.

Both in the beginning were focused on surviving.

Both also have honor.