Classes are not solo only

[Asiaine]

The only job I don't see worth soloing on is BLM, every other job seems to get enough survival skills for their own soloability.

You can solo a bit on BLM. Just generally not as well as THM. A BLM can still heal (Second Wind, and Necrogenesis), and benefits from Sleepga. But in general, unless you really need Sleepga, there is not that much benefit over THM. And, due its interesting implementation, there is not much stopping you from going as THM, /job on, sleepga, /job off.