How does radio bandwidth restrict the choice and use of science payload on interplanetary probes? I asked a question here about returning to Earth a physical memory capsule along with soil samples, as a complement to radio operations as today. This might return a much larger amount of data compared with radio today, but of course only at the end of the mission.

How useful would it be for a sample return mission like Mars2020 or Hayabusa2, to be able to return much more data? Would the choice of instruments change to allow for higher sampling rates, higher resolution, more filters et cetera? Is Big Data science instruments from an interplanetary mission even a possibility, or is today's bandwidth good enough for any conceivable payload?
Sample returns are expensive and risky.  Radio is simple and reliable.  Radio bandwidth on a particular mission is determined by several engineering tradeoffs.  Higher bandwidth requires either larger antennas, more output power, or more complicated processing.  

Spacecraft are typically limited in mass, power and compute capabilities. What most missions have plenty of, is time.  Lower bitrate takes longer, but allows more mass and power to be used by other experiments.  This is often a highly desirable tradeoff.

Missions like New Horizons that have a fairly limited time to record lots of observations do so to a data storage device, and then spend months or years relaying the data back to Earth during the long coast to the next target.