Not sure what the pace of the hydrobots are right now but last I heard they were going to do a test on Lake Vostok in Antartica.

A Europa mission won't leave earth until 2016. That quite a while as far as developing technology. And I know radiation shielding is a biggie for the Vision. Perhaps they can come up with an orbiter that will last much longer than you think.

If hydrobots are not good to go than a modified MER type rover would still rock!

Then there's the deep impact approach. Drop a few metal bowling balls from orbit at the thinnest part of the ice you can find and have the orbiter scoop up any ejected material and analyze it.

Saturn's system has Cassini probably for the next decade AT LEAST. If we're stuck with a choice of Eruopa or Titan, then Europa has to be the winner. We need to get a good look at that ocean.

Ideally we could do both and much more.