I just finished building my first Hellivator. It is a modest one, comprised of a 3-block wide shaft with periodic wooden platforms spaced roughly before my fall damage threshold. Some torches light the path downward. And I still need to go back through and tweak the spacing of a few platforms, as I take a bit of damage when riding my express wonka-vator all the way down to the fiery underworld. But it sure beats crawling through the dangerous labyrinth of tunnels and passages I hollowed out so much longer ago.
But now that I'm down here, amidst the lava pools and demons, I'm wondering what to do next. And so it goes with Terraria.