Can it be considered somewhat easier to run out in 8B since you're free to shoot any ball in your color group?
*IF* (big stipulation here) your opponent's balls weren't still on the table, yes. That is to say, if your opponent tried to runout, and failed, leaving you a Marianas turkey shoot, yes, it is easier to runout in 8-ball, because as like the die-hard 9-ballers like to say, "you can shoot at any ball you want."
If (and the more likely scenario) however, your opponent's balls are still on the table, and you're trying to navigate around them, the runout is actually more difficult, especially as you start clearing your category off the table. Unless you plan your run so perfectly such that each shot is a stop shot, the deeper you get into your run, the more difficult it becomes to get position on the last couple balls, and finally, the 8-ball itself.
To me it's a wash and completely depends on how the balls spread after the break.
That is the case with *any* game. I've seen "breaking safe" happen in any game, including 14.1 -- where the break ball was pocketed beautifully, the rack opened up, but the shooter was left no shot.
The real challenge would be to play 8B and finish your color group in rotation.
I agree. But I don't know how common this is, because of the difficulty of execution. Remember, unlike 9-ball where there are no "off-limits opponent's balls," you would have to contend with navigating around your opponent's ball category, in addition to running out your category in rotation. Add the variable of the break into this, and you have probably one of the most difficult games on the green playing surface to execute runouts in. That would most definitely be a safety game, for sure.
-Sean