My situation:

Wife is Australian, we live in Memphis TN, USA
Two kids, one 4, one 8 months.

The "Plan" was/is to fly to Australia every other year. To keep mama happy, I need to be more diligent in making this happen.

On a quick search, it seems that the best points/mileage non airline affiliated card is the Capital One No Hassle Miles Ultra, earning 2 miles per dollar spent.

I can put quite a bit of purchases on the card, maybe 40k - 50k in a year, possibly even more.

Any suggestions on whether I would be beter off with this or an actual airline affiliated card?

One possible advantage on an airline card would be the ability to purchase an economy ticket and upgrade the international portion to a higher class. But I wouldn't be able to accumulate the points as quickly at 1 - 1.5 points per dollar.

Thanks for any and all suggestions
Tracy