Somehow a tenant punched a good size whole in the middle of one of the kitchen wall cabinet doors. It was adjacent to and above the kitchen sink. Since the door is a 'hollow core' type built in the 1960's, finding a replacement that matched size and color was tough, even with a couple of trips to 'Restore'.
The fix: We enlarged and squared off the hole to about 12x18 inches, then inserted a piece of fancy glass from a remnant the local glass shop had and then trimmed it out. We made it look like the glass and the door was a kitchen accent. Looks good. If we'd been thinking, we would have done the same to the cabinet on the other side of the kitchen sink so as to add better balance.
That is a good idea! For resale you might go ahead and do that to the other side as you say for a better balanced look. If you ever want to resell it makes for a more sell-able property.
That's a practice I have used. If you can't match it, make it totally different and chances are no one will ever know.