I found Ecclesia too damn hard and the boss fights repetetive.
Can't Speak for DS Chronotrigger, but I converted my ps1 one to the PSP and still reckon is awesome.
Remember, Graphics maekth not a game, otherwise the DS wouldn't out-sell the PSP...
As someone else said, Zelda is awesome, but short. Ive been playing Winds of Nostalgia (in japanese) and its pretty cool. I believe its still slated for english release.