I think a little of both, Tom.
Smaller planes, such as the Canadair CL-145 have advantages in their quick reload time: dip into a lake, scoop, and back you go to the fight. Works well in Canada, with more lakes than the western US.
Planes such as Hercs, Neptunes, and Trackers have limited loads, and long transit/reload times.
The idea with a Supertanker is either one big drop for strategic fires, or lots of tactical drops (since capacity is huge, and loiter time significant).
The drop-aiming system is supposed to be a force-multiplier, too.
I watched Evergreen's Tanker program with interest, as a former Evergreener. Boeing was involved as they saw a huge worldwide market for older 747 conversions. The story was.....they (Evergreen) didn't have the right connections. For some reason, whether political, or if Delbert Smith was charging too much money, they were rarely invited to play, even when there were big fires (Colorado in 2013 comes to mind), where there "...weren't enough tankers available..."
It only played in a few big fires. It performed very well, but was never utilized to its full capacity.
And that is a shame.