Ahoy!
I expect few things from ETS2.
First, some roads could be turned into official hidden road that is marked; also those hidden roads remain unmarked nowadays could be officially marked.
Second, more flexible in truck and trailer decoration, such as Pacific Solid rim cover able on trailers, able to put two decorations in same position that they are not conflicted each other, or paint job like BCE/Sunrise able on 8x4 chasis.
Third, more new trucks and new type of ownable trailers, also update in type of AI traffic.