As with everything else, it depends on where and when. Let's say France in pre-roman days, I'd say a general had the tougher "job", since it was much easier moving by sea than through the endless and roadless forests that covered most of Europe. If we jump to the WWII though, I'd say a general had it easier thanks to the good infrastructure and not having to worry about mines and submarines (of course things could be mined or booby trapped on land as well, although it was less common during WWII than during later conflicts).

There really is no way to answer other than by "It depends".