Any suggestions on how I could use 24140 Delta Miles I have sitting around which seemingly refuse to die?

Any suggestions on how I could use 24140 Delta Miles I have sitting around which seemingly refuse to die?

24,140 is too low you can't even get to Bali on Garuda (Sky Team's  Asia Pacific partner).

Unless you find yourself in Europe or North America and need to fly regionally, I would write-off those miles and imagine they don't exist. 

Even within Europe and North America flights are so cheap I wouldn't bother hunting around for a redemption. Plus the taxes you would have to pay in addition to the mileage redeemed would be comparable to the cost of an outright revenue ticket!

Can you fly VA but use DL's flight no, and put points towards the DL account, to build up the kitty till you have enough points to do something?

If you don't have any particular need for them you could always donate them.

https://www.delta.com/buygftxfer/displayDonateMiles.action