Processes for converting methane and/or other hydrocarbons to synthesis gas (i.e., a gaseous mixture comprising H2 and CO) are disclosed, in which at least a portion of the hydrocarbon(s) is reacted with CO2. At least a second portion of the methane may be reacted with H2O (steam), thereby improving overall thermodynamics of the process, in terms of reducing endothermicity (ΔH) and the required energy input, compared to “pure” dry reforming in which no H2O is present. Such dry reforming (reaction with CO2 only) or CO2-steam reforming (reaction with both CO2 and steam) processes are advantageously integrated with Fischer-Tropsch synthesis to yield liquid hydrocarbon fuels. Further integration may involve the use of a downstream finishing stage involving hydroisomerization to remove FT wax. Yet other integration options involve the use of combined CO2-steam reforming and FT synthesis stages (optionally with finishing) for producing liquid fuels from gas streams generated in a number of possible processes, including the hydropyrolysis of biomass.