I don't have any specific star finder adventure paths but I have been writing adventures for about 35 years and am almost always the dungeon master in my group. I have over time come up with a few things that are important:
1. DONT RAILROAD THE STORY - don't force the players down one route - they need to feel like they are solving problems and in charge of their destiny - not riding a train down your adventure. You have to provide adequate clues and motivation for them to continue. I played a game of 1930s last week where everything was in place but the players had no motivation to go down the story path - no reward, no attachment to the story personally....make sure you have something there.
2. DETAILS DETAILS DETAILS - I always want my player to feel like they are really in the world instead of playing a game and the way I do that is I make sure I have enough details in my head about little things that they feel like they are on vacation in a foreign country -lots of things are new. In the same game I mentioned before, our DM then had some of the adventure at a horse track in the 1930s and he had a thorough understanding of horse racing, bookies and bettering - and other aspects of 1930s life -it made the story awesome!! Obviously in Starfinder its not historical but .....details make the game
3. AT ALL COSTS - Stay away from Cliche
4. FOCUS ON HOW PLAYER FEEL - I like to make my players feel things, so use a lot of foreshadowing, create anxiety, create motivation to get their hands on things, feelings of revenge...they should be driven by strong emotions
5. NPCs are critical - I always have an NPC in the party that can provide some subtle direction and knowledge to players, and can act as the voice of the narrator -aside from that all the NPCs should be well developed people, not cardboard cut outs - I almost always base mine on someone I known my players don't.
Now as for how to WRITE IT - if its not a dungeon, I usually outline a kind of flow chart or script for what happens, and I make sure that when I am running it I have the material I need - names are hard to make up on the spot (people, and places) - as is any details players might like - I make the notes so that I can run it smoothly - crude maps if needed,