Like BRTV, I liked the idea of this one but felt it needed a lot more development. The need to scroll through all the objects was really annoying, especially because the interface glitches out if it gets too long. The game also felt too short -- I had a bit of a "Wait, it's already over?" moment when I beat the final mission.
The game felt a little too easy in general. I expected there to be some sort of limit on how often you could distract guards with laptops and cellphone hacking, but it's trivial to keep them constantly occupied. Similarly, cameras are trivially easy to hack -- I think I only got caught the first time I encountered one. (I also completely forgot that monitoring doors made them impassable to guards -- some way to review your abilities and what each object does wouldn't go amiss, I think.) There also wasn't any real penalty for failure, since you don't have any kind of ticking timer or drain on your money in the tertiary loop, and if Trilby subdues a guard you can explore the rest of the level with complete impunity. The game definitely needs more threats, like maybe a constant reinforcement of guards or a timer for the whole mission.
I also thought the minigames were a bit too random, or specifically the type of minigame you got was too random. They all take very different lengths of time to resolve, and obviously the ones that require you to type with specific sectors are harder than the ones that are totally random.
Still, I liked the core concept. The framing story was neat, Casey's social awkwardness was #relatable, and it was really cool to get something focused on the nerdy support character over the typical action hero. And I did find the typing minigames very fun despite your worry that they couldn't hold the game -- I was impressed by how many twists you were able to make on the concept to keep them from feeling too samey. I agree with your idea that the game could benefit from swapping to different character modes, especially since as it is Trilby does so little. I'd be interested if you planned to develop this further.
P.S. I'm sure a million people have told you this already, but Hacknet and Beglitched sound like games at least tangentially related to the concepts here. Add them to your compost pile of ideas, maybe.