So I managed to find a reason why #TheVela feels so different from #TheExpanse.
The world's framework feels similar: a solar system, with sublight interplanetary travel possible, but usually not fast, using both gravity assists and high-g burns. The outer planets as basically colony worlds, exploited by the inners for water and other materials. Refugee waves if something goes wrong, and prejudice against outer planetary folk in general. Political systems not being democratic.
(1/n)