A 4-2 win on the night for Unai Emery’s side saw them wrap up a 7-3 win on aggregate and book a date with Premier League rivals Chelsea in a showpiece event on May 29.
Aubameyang will be expected to lead the charge for silverware in Baku, with Arsenal still eyeing a place in Champions League competition for 2019-20.
Their leading man has found the target 29 times this season and is on course to match the likes of Henry, Emmanuel Adebayor, Robin van Persie and Alexis Sanchez in reaching the 30-goal mark.
“I have said it before but he is the closest thing to Henry and he is proving that,” former Gunners defender Keown told BT Sport of a prolific forward.
“We are getting out of our chairs every time he has the ball. Let’s credit Emery as well for playing both of those strikers [Aubameyang and Alexandre Lacazette] and [Mesut] Ozil as well.
“He was cup-tied last year and boy did Arsenal miss him. He was [Eden] Hazard-like running with the ball at times.
“He became a top player for me [against Valencia]. I've said he is the closest thing to Henry and he showed it.”
Arsenal fell behind inside 11 minutes against Los Che at the Mestalla, but saw Aubameyang quickly restore parity.
Lacazette then put Emery’s side in front before his strike partner rounded off the scoring after seeing Kevin Gameiro record his second of the game for the hosts.
Ex-Arsenal striker Hartson was another to be left impressed by the efforts of a fearsome attacking unit that offers hope in north London for a bright future.
He added, while focusing on the Gunners’ opening goal against Valencia: “Aubameyang runs under the initial header but his reaction is magnificent.
“He backs Lacazette to win it and that is a brilliant finish. He has beaten the goalkeeper on his favourite side. He shows him the other side of the goal but it is a brilliant equaliser.
“Aubameyang had his best night in an Arsenal shirt. He was on a different level to everyone else out there.”