Spirit Tracks is actually a very good game. Naturally I completed both, and even played Spirit Tracks a month or two ago. Before the HD remaster, I found Spirit Tracks better than Wind Waker. Anyway, they're not the best handheld games nor are they the worst, though Phantom Hourglass was very disappointing for a Zelda game.
Link's Awakening is by far the best and even beats all but one of the console games to me: LA > ALBW > ST > OoA > OoS > PH > TMC > FS