As I live in Asia much of the year, I often bring lots of stuff back from the US. I rarely bring boxes as they seem to get beat up, and often aren't covered if damage occurs to the contents.

You can ask relatives for old, but large sturdy luggage, or check thrift stores. I bring glass bottles of food items, like olive oil, olives, etc, and when packed properly, I've never had a breakage.

I do, however, have a number of very large suitcases that I can stuff with as much stuff as possible. Last week, I arrived with 3x 32 kilo bags, plus a legal size, but not lightweight carryon, plus laptop bag. Say, another 35 kilos.

I had actually packed one checked luggage a bit overweight, at 40kg, so had to redistribute it quickly. Luckily they didn't weigh my F carryons on CX. And I didn't have to pay any luggage fees.

Often it's worth flying in a higher class of service to avoid luggage surcharges.

If your clothes are bulky, but light, I'd investigate SpaceSaver bags or similar. You can easily fit 3 times more stuff in a bag, with some fluffier items. If you can only bring 23kg bags, check the surcharge for 32kg bags. Might be cheaper, and don't forget that if you are elite, you may get a larger luggage allowance.