My friend and I went thru these as well. He's a SMN main but swapped to SCH just to get thru the story and he said he stopped bothering to Heal in both dungeons. The 1st dungeon didn't do enough damage to proc his Excog with a random GNB as the Tank and the 2nd Dungeon was WAR so that went as expected. For the trial, it's only reasonably fun for now because people don't know the mechanics but most of the mechanics aren't that hard to understand and dodge, so I expect it to be just as dull as any other trial as more people run it and get familiar with it.