It's good for solo if you are a careful and strategic player. It's not good if you like rushing through. If you die your stuff stays there in a tombstone, which makes it challenging to get back solo, but you can usually sneak and grab. If you get stuck, check the guides. Be aware that every new biome will make you feel like a newb all over again, which is part of the appeal, but don't think that your armor from the last biome will let you walk around without worrying.

You probably will build more than one base, but teleport materials start being available in the second biome.

I've played it solo the whole time. I'm up to 900 hours now, after multiple runs. The large procedural map means that exploration will always be important no matter how many times you play,

Added:
Meadows>Black Forest>Swamp>Mountains>Plains>Mistlands Don't go out of order.
The pickaxe and the hoe are the two most important tools for base defense.
Don't land your boat in the swamp.
Let's see...there's another one...barricade around Moder's shrine as if it was your base.
I think that covers the main points that people get stuck on.