3.3.2.1930905700 - Large, Crimson, Master Mode.
Alright! So I'm fairly certain the exact thing you want is impossible because either you get Crimson near spawn or near another biome, there's no in-between. However! I have found what might be my favorite seed! To put it in words:
Left side is COMPLETELY Crimson free! Jungle's that way as well. Left side also has a fairly long stretch of flat-ish Forest ground which is nice, and 2 pyramids (although they can't be seen from the surface). There's three deserts separated by tiny portions of grass. The first one is a "fake" desert with an Oasis so it could be cool to include in the town design since it's mostly safe. Then you got the real one, then another fake one. Past that, three large living wood trees, then the jungle.
Right side has a small bit of flat-ish land and then immediately one large hill. But that's good! Because a bit further past the hill, a huge Crimson land awaits, which makes it a natural defensible post. The Crimson does somewhat hit the Snow biome, but it doesn't go too far into it (Hint: Once you hit a large pool of water, you're safe to dig down). Now, I know it's close to spawn, but hear me out - this is the ONLY Crimson on the whole map pre-hardmode!
It kinda feels like the world is split in half because of this. One "Evil" half, with Crimson and the Dungeon, and one "Pure" half, with deserts, jungle etc. I really hope that in hardmode the left side will turn to Hallow. That would really nail in the "Pure vs Evil" aesthetic the map has going on.
