I guess, yeah, it was pretty radiant.
Unfortunately, Radiant Historia deteriorates in quality in its second half. More absurdly-annoying enemies and enemy abilities start to show up, including the super-fun "chance of instant death" ability. Most party members continue to get shuffled randomly around -- including one ridiculous event which has party members spontaneously reappear and fight, not even yielding a chance to update their equipment. A few story sequences require irritating re-treading of the world map, and the last couple dungeons become labyrinthine and thoroughly tiresome. And the story itself goes a little off the rails in its final chapters, losing some political intrigue and character drama in favor of familiar JRPG magical-planet-destiny stuff. It's written well, and not "bad" really, but not as enthralling as the game's earlier material.
I found myself getting bored of dungeons and combat as the game wore on - really, I think it is just a bit too lengthy - which was no help when I realized that I had become under-leveled. This can be mostly overcome with some strict equipment choices (fitting the whole party with defense-boosting accessories to keep them from being murdered instantly), but the game is fond of throwing out bosses and mid-bosses that just trample over stats that aren't quite up to snuff. What stings the most about Radiant Historia's level curve is that it comes to ruin the game's inherent non-linearity: although there are many instances where either the Standard or Alternate timelines have content to pursue, one of them might require a much higher level to proceed -- that is, it's scaled on the assumption that the other timeline is tackled first.
And as for party makeup, even if out-of-party members gained experience at the same rate (and were more regularly leveled-up when the story makes them go missing), there are still fundamental issues with how skills are distributed among them. Marco, the closest thing to a healer archetype that there is, lacks a few critical healing skills that other, more offensive characters happen to have. Raynie learns the best offensive magic spells, but isn't able to equip good magic-boosting items. Stocke is still the only character who can push enemies leftward and rightward. Aht's and Eruca's magic libraries are so ridiculously situation-specific that they just aren't worth keeping around.
Still, despite these wacky design decisions, I was able to make my way through the game without any explicit level-grinding. I had fun uncovering the game's plot, and the battle system - when it wasn't filled with completely stupid enemies - was generally enjoyable. Radiant Historia was a fresh and entertaining experience, and I'm overall pleased with it in spite of its flaws.
Better than: Avalon Code, Nine Hours, Nine Persons, Nine Doors
Not as good as: Final Fantasy VI
Per the "events" count, I skipped a ton of sidequests: but I've had my fill of the game just getting to the ending.
Progress: History complete, level 59, 175/236 events