Since I'm already keeping a diary of Demon to help me learn from past mistakes, I might as well share my journey here. I apologize if this is a little dry, but I tend to die a lot so as time goes on I've streamlined the note taking process. Hopefully this will be helpful to people who are just starting out and trying to learn how to learn the game.
Chargen:
Eye of the Dragon
Personal favorite for aesthetic reasons, plus removes a major source of RNG. I realize this isn't the best or most popular artifact, more experienced players with actual wins seem to prefer the other artifacts.
Healing
Body resistance is one of the most valuable due to how nasty AND common the status effects are. The only better resistance is Mind, which is rare in the early game but consists entirely of status effects that remove control from the player.
Healing also helps with some links, especially patching up damage and escort.
Healing is useful on monostat builds, as it scales solely off of Magic.
Tulpa
I prefer the reliable DPS of the familiar, but Tulpa was missing from my bestiary so I threw him in. Starting demons get replaced pretty quick regardless.
T1
Cleared without issue. Short one demon due to running into goblins and slimes early, which are too expensive to be worth recruiting too many of. I wound up taking only one goblin, though in retrospect I regretted missing out on the get-out-of-status-free card the slime offers.
Notable brands include SP -1 and SP -12%, might make use of those later.
Roster:
2 Summoner
2 Tulpa
2 Zaltys
2 Zaltys
2 Goblin
2 Echeneis
T2
Found a Buruburu on a corpse, made an attempt at an early Ogre. I played stingy and failed to get the Ogre, should have spent items or copied dps abilities to my demons. Wound up getting rid of a Faery since she was missing the most synergy (Dancers Boon requires Evasion Up) and had overpriced heals.
I normally like combining Zaltys and Faery to make stat agnostic luck-healers, but I decided to dump that strategy this time because it's extremely SP and time inefficient. Burst damage is usually better than endurance, especially with hit and run tactics.
Roster:
3 Summoner
3 Tulpa
3 Zaltys
2 Goblin
2 Echeneis
1 Sankai
1 Buruburu