vote for sinbad's one , it does not look too hard to build (everything already exists) and looks quite good (except the green chicane ...).
Dear devs, please
in this one there is some bits of the rallyx track that will need to be transformed to tarmac ... or it can cause an aweful amount of deadly accidents...
the tunnel isnt really underground... it is sort of like the one in the singapur racetrack , it goes under the grandstand