I would like to see a cargo so heavy, that it is impractical to transport it behemoth loads at a time.

It should be valuable only in grey, requiring transport across multiple systems of high contention. It should have a mass of about 10k per cu, and be worth about 2k+ profit per 1k of mass per jump.

The objective being a trade route that is achieved not by stealth, but rather by brute force. You use a combat ship to transport it. if you are challenged during transport, then you by necessity have to drop it to run or fight, but if you defend it, the aggressor is also forced to deal with you before even considering picking it up.

I like it. 20k per cu profit isn't bad, but I'd bump it to 25k+ to get more fighters in on the deal. You could also up the weight a bit to compensate.

just make sure to keep your foot off it

Interesting idea. We certainly need more incentives to get players trading in Grey space. How many cube per unit?

Do it! Something I can do when nobody is in B-8... make more money :P