I agree with you that it might be an opportunity down the road to do vehicles if it takes off, though to be honest that's probably a longshot. But, who knows? I got myself a MIB Power Ship and Trigore to use with them just in case.
With the Power Lords, I would love 6'' figures as much as anyone, but the economic reality isn't there. There's a reason the 4H have struggled to keep their 7th Kingdom/Gothitropolis lines going and that they will be turning to Kickstarter for the release of the Raven. It's just financially VERY difficult.
But with the Outer Space Men, they've found a successful way of doing a toy line. They are 3 3/4'', Glyos compatible, and come out in waves of variants as well as the fully painted wave to make the most out of the mold cost. Although some people (more than just teemu!) might think it's a "FAIL" the truth is if they don't do it this way there would be ZERO Power Lords lines to call a fail.
I'd rather have a cool new line (and supposedly, media!) than no line at all. And if the smaller line takes off then there's always the hope for a 6'' line later.