I started a campaign a few months ago, tell me what you think.

The main antagonist is the cult of Tasieh, a lawful evil deity called the "crystalline lord"

The party consists of a cave elf sorcerer, a fairy paladin, and a bearfolk barbarian. I have interchangeable dmpcs consisting of a dwarf bard, an aaracockra wizard, a fairy wizard, and a human cleric.

Session 1: Party has a run-in with a member of Tasieh's cult, nearly dies. Barbarian insults police, rolls nat 1, and all get sent to prison.

Session 2: Party, in prison, meets Aaracocra named Ress Aquamarine. Ress helps them escape through a cave. He leads them to a mysterious building in a jungle that transports them to an all-bird island.

Session 3: Bird island antics, new favorite npc (seagull named KAARL) Leaves island

Session 4: Party tries to find informant who has information about cult in a tavern, cult tries to capture informant. Barbarian starts a tavern brawl and picks up the informant, a small gnome woman, and carries her to safety. Information leads us to sail to another continent, but the boat is wrecked in a storm leaving party on an island called the melodic tempest.

Session 5: Info dump. there's a magical border around the island preventing anyone from getting off. Every night, the time skips forward, changing everything but the people there. Oh by the way there are hundreds of people there, all shipwrecked. Also, there is a war with the blights and evil druids. The time skips are supposed to grow the druids' plant army. Party stops timeskip

Session 5.5: one shot with the barbearian.

session 6: Sidequests for two people who care deeply about the other, but think the other sees them as "just friends"

Session 7: cozy tavern vibes and Weird npc

Session 8: RESCUE!!! And new quest giver, Queen Lorelai.

All caught up. Give me feedback?

I love the story, 9.5/10. KAARL the Seagull is my favorite part. but is the cult of Tasieh mentioned at all in session 8 or maybe gonna be mentioned in session 9?

They are mentioned, because the party becomes the queen's delegates to systematically destroy the cult. Also, party needed a breather.

Sounds like a railroad. 

If your players are happy, those are the votes that matter.

My chief concern are the DM-PCs.  Typically, the DM controls the setting and NPCs, while the players are the active agents in the story.  DM-PCs have a tendency to steal the spotlight, which is why they typically have a bad rap.  Are you running yours as full characters alongside the players, or are they more like NPC hirelings traveling with the party?

Quote from Avohei >>

Sounds like a railroad. 

 How so? Any plot that takes so round-about a path to the actual plot - confronting the cult - can hardly be a railroad.

Quote from FayetteGamer >>

DM-PCs have a tendency to steal the spotlight, which is why they typically have a bad rap.  

 I have the opposite experience. I find GMPC's - or variations of NPC hirelings, which is in fact the exact same thing - tend to be used as human shields. Players will be like 'we push Ned the NPC onto the pressure plate' and I'll be like 'no you don't, Ned is back at the entrance minding your horses and collecting wood for a fire, so he can cook your lunch.' NPC's of any kind are strictly denied access to any game changing participation - unless it's life or death. I had this one encounter where a panicky NPC tossed a vial of acid that finally stopped the regeneration of a monster the PC's kinda failed to realise wasn't dying by the method they had selected (which was 'it isn't dying, hit it harder. NO, EVEN HARDER!')

Quote from Acromos >>

Quote from Avohei >>

Sounds like a railroad. 

 How so? Any plot that takes so round-about a path to the actual plot - confronting the cult - can hardly be a railroad.

Quote from FayetteGamer >>

DM-PCs have a tendency to steal the spotlight, which is why they typically have a bad rap.  

 I have the opposite experience. I find GMPC's - or variations of NPC hirelings, which is in fact the exact same thing - tend to be used as human shields. Players will be like 'we push Ned the NPC onto the pressure plate' and I'll be like 'no you don't, Ned is back at the entrance minding your horses and collecting wood for a fire, so he can cook your lunch.' NPC's of any kind are strictly denied access to any game changing participation - unless it's life or death. I had this one encounter where a panicky NPC tossed a vial of acid that finally stopped the regeneration of a monster the PC's kinda failed to realise wasn't dying by the method they had selected (which was 'it isn't dying, hit it harder. NO, EVEN HARDER!')

 That's the way to do it correctly.  Background support characters that are neither active agents of change, nor suicidal pushovers.  Those are party NPCs.

The term DM-PC typically refers to when the DM controls a character in the party, who does act with agency, typically because the DM wants to be a player in addition to controlling the world.  That causes problems that I expressed concern over.

Quote from FayetteGamer >>

If your players are happy, those are the votes that matter.

My chief concern are the DM-PCs.  Typically, the DM controls the setting and NPCs, while the players are the active agents in the story.  DM-PCs have a tendency to steal the spotlight, which is why they typically have a bad rap.  Are you running yours as full characters alongside the players, or are they more like NPC hirelings traveling with the party?

 The dmpc's function as NPCs. They also allow me to have a little fun playing, but they don't talk much. The players can rp with them, and they give a hand in combat occasionally. They also have backstory and lore to explore. But, mostly, yeah. Npcs.

Just read this. The side quest idea for the two PCs who like each other and don’t know it sounds awesome.

Good idea, but you’re going a bit too fast, spend some time on worldbuilding and less from the main story. This makes it a truly immersive experience, also spend 1 hour a week at least taking notes for the next session, this will really help

Nice