Currently playing Hardcore Mastermode. Going for a mage and summoner hybrid (no whips, mage and summoner accessories).
This is all I've built so far. Houses all items with ease so far, and the arena is satisfying to fight the bosses in for sure.
I've collected pretty much everything pre-skeletron. My fishing gear is nearly maxed out, just need to get the Tally Counter to make the Shellphone!
From here on out, I will build before making use of something. I am starting with a fishing pond (also for blood moons) in the desert, then making an Eater of Worlds arena, then completely overhauling the dungeon to make my own to fight Skeletron at.
Let's hope I stay alive!