Special Cargo's payout is still fine, but simply adding a bonus would be fantastic; about a 5/15% chance of applying a multiply bonus that adds 10-25-45% profit, depending, but since the chance of receiving a bonus is low, this is fine because that is how it plays the 'odd'.
Also, the payout for special cargo is currently extremely low; everyone will agree that since it's 50-100k and sometimes 200-280k, that shows its rare value; others nah as stated(, it makes the special cargo worth more that way.
This is another part of the idea derived from my other suggestion ideas, but modified for 'Special Cargo'
Special Cargo Profit Multiplier (Odds)
With increasing inflation, I agree with Ast. The "big" payout jobs should have bonuses to compensate for the rising inflation.