I've been listening to the Haitink symphony cycle (which also has, of course, some of the tone poems).
The first three symphonies were all new to me, and I'm growing to love them, if not as much as the latter three. Eminently tuneful, attractively scored, quite colorful, lacking the depth of the final 4-6, but always fun.
Four, however, remains my favorite, as close as music gets to perfection.
I put Tchaikovsky firmly in the realm of the greats--his occasional problems with form notwithstanding.