i think thats being overly paranoid. malware would not just randomly appear in an executable you made, it would have to be put there by an attacker who either compromised your computer or itch.io itself, if either of those happened there would be much bigger problems to worry about. the only precautions developers need to do are informing users to only download from the official sources. the only other thing i can think of for security on the developers side would be including a file checksum, so users could verify they have a file that has not been tampered with. it makes sense from the users perspective to be cautious about what they download and run, but i cant see how an honest developer making their game browser only changes that. in the end its fine to make a browser game as long as it does not limit what you want to do, and i dont have a problem with your decision.

i like the game so far, but it has some quality of life problems that hinder the fun. to start, some simple tasks in the game are more tedious than they should be. picking up buildings requires clicking on them to destroy, and then another click, manually moving it to your inventory, and a final click to place it in the inventory. there should be an option to directly pick up buildings and automatically place them in the inventory, and the same goes for items placed on the ground. it would also he helpful if you could grab items from containers and automatically place them into the inventory. if you had to rebuild a part of your factory it could get very time consuming having to destroy the buildings and grab every little piece. one last little thing, if the conveyor size was the middle size by default it could save a lot of clicks since players will likely need something bigger than the smallest.