Thoughtful ways on how to give my Wife her engagement Ring

I’m not sure if this is the right place to post this, but I’m looking for ideas on how to make giving my wife her engagement ring special.

When we got married 19 years ago, I could only afford to buy her a wedding band. It’s a beautiful band, but I always wanted to give her the engagement ring she never had.
My wife’s 40th birthday recently passed, and my original plan was to upgrade her with the ring then since turning 40 is such a big milestone. Unfortunately, I had to undergo surgery, so I had to change those plans. Before her birthday, we went ring shopping together and had one custom-made, but it wasn’t ready until a few weeks after her birthday.

Now I’m torn. Part of me feels like I should wait until our 20th wedding anniversary next year because that’s another huge milestone. The other part of me feels like she’s already waited 19 years, and I don’t want to make her wait another year just because the timing wasn’t perfect.

I’d love to make the moment meaningful rather than just handing her the ring. Have any of you surprised your spouse with a “late” engagement ring or recreated a proposal years into your marriage? What are some thoughtful ideas that would make this moment memorable?