Are you (generic you, not OP in specific) solutioning for cheap or solutioning for mobility/convenience?

In addition to the approaches OP already identified, I'd like to add a couple points on the solutioning for mobility/convenience side.

- Use a freight forwarder. Japan is the prime example. Hotels, even hostels, are well aware of the practice and often have the forms to ship your luggage to your next destination.
- Use surface transport more. Night trains, night bus saves money and generally are generous with luggage. The Midwest logic in me also have no problem picking rental cars, pack all you want onto the car. I would drive 12 hours instead of taking of a ULCC. So be it if I won't need the car while I am spending 3 days inside the major city, I can pack everything in it when I drive to the next destination.

Unless you have irreplaceable items in your checked bag, any delays/lost also shouldn't ruin a trip. It's a mild inconvenience.
Buy some new clothes, file a claim with lost/delay luggage insurance then go on with the trip. I'd imagine Flyertalker armed with travel credit cards all have some form of coverage. (Exception: Self-connects. You might not have time to even stop by the baggage office or risking that next segment)