Use of "that was" in the active voice

I agree with all the comments but would insist that your original sentence is just fine the way it is. You can add more detail to make it a more formal description but it adds nothing and takes away a little bit here and there until it has no charm to offer. Leave it be.

What does "period charm" mean?

What do you call a microphone that is held beside the face?

"Right tol loor rul!" Meaning - Dickens, Dombey and Son

Idioms or metaphors for "I'm curious to know why, but it seems I'll never know"

Usage of "self-absorbed" to describe metaphors [closed]

Synonym for "geek" (computer geek) with positive connotation

A way to describe the sound a car makes when you're cranking it over, but it won't start?

The difference between "qualified to" and "qualified for" [duplicate]

Word for when I present a graph to support my point but it refutes it? [duplicate]

Are “thought” and “had thought” both correct? [closed]

Origins and meaning of "can you not"

What do you call making a sound of derision or contempt by blowing through closed lips (but not using the tongue)?