I will post e-mails I receive (always with permission) that express well thought out views on future planetary missions and roadmaps. The following comes from Bruce Moomaw on future flagship missions.
[referring the the great new images of Enceladus, Bruce writes:] Let's also not forget that the Titan Flagship mission as it's now designed would include four low-altitude Enceladus flybys (100-200 km) during its Saturn orbiting phase before entering Titan orbit -- and some of its Titan-oriented instruments could provide a surprising amount of new Enceladus information. In particular, note that it includes a subsurface radar sounder and an aerosol-analyzing mass spectrometer with a peak AMU range MUCH higher than Cassini's, allowing a search for really complex organics in the Enceladus plume particles as well as in Titan's upper atmosphere: http://opfm.jpl.nasa.gov/files/1.2_Reh.pdf .
As for whether we should go for the Europa or Titan mission first: damned if I know. But let's remember that -- as the latest Planetary Science Subcommittee report points out ( http://www.lpi.usra.edu/pss/report/nacReportOct2008.pdf , pg. 4) -- whichever one is rejected for this round may well NOT be the SECOND big non-Mars Solar System flaghip mission chosen. In particular, it may have competition for the next round from a Neptune orbiter/probe mission (although it's clear that the so-called "Venus Flagship Mission" now actually consists, probably wisely, of a flock of separate smaller missions that can be flexibly scattered all over the place timewise). In short, whichever mission doesn't get the nod this time around -- whether Europa or Titan -- may not get off the ground for a long, long time.
(As a wild speculation, could this be a very indirect point in favor of picking the Jupiter-Europa Flagship? One important component of the Titan mission -- the Titan lander -- could be flown separately at relatively low cost IN ADDITION TO the Jupiter-Europa Flagship, at about the same time, if it takes the form of a short-lived Titan lake organics-analysis boat dropped off by a flyby craft. After all, that's one of the Stirling-powered Discovery proposals, and it could be flown as a solar-cell-powered mission too. It would also be an ideal opportunity for a NASA-ESA collaboration. By contrast, you can't seem to break off any comparably low-cost chunk of the Europa Flagship mission and fly it separately at about the same time as the Titan Flagship.)