White plays pretty good Go, with good fuseki fundamentals, a focus on surrounding and killing through placement.
Improvement may lie in good shape and figuring out what/why to attack.
The kill at

is not so big, since Black got a big corner and it is not so clean either: what happens if Black executes a R8-Q7 combo? Is he captured at all?

at Q7 would have been better shape.
A high influence move like

would surely be more valuable in the corner (C5) but it's consistent with the style.
Attacking with

looks like a classic move but Black's shape is already hard to attack and he should have no problem living while taking points away from corner and side.
I thought

was not so bad actually. It's White's vital point.

was an atrocious move, a sign of Black still being a beginner

is VERY clean, not to say slow. It looks like a declaration of victory. With C5 still available, that's a fair assessment.
With the 3rd kill it was indeed game over IF Q8-R7 doesn't work (and if it does then C5 is still there for the taking)