1. Fighters fixed for next update.
2. I don't mind that you can use mouse to look through a holo, you still have to guess it's a holo - even though ship designs are currently too basic to hide it. I still find it interesting to fight against and can make use of the AI effect. I don't intend to have every block available in the full game, and this block is unlikely to make it into the opening selection. But I see no need to cut it.
3. The enemy nanites can stack, it just happens rarely. I've added a condition preventing clouds from moving into an area with a trigger already in it (bullets / clouds / fuel). This should make things clearer. Adding a time limit means natural clouds can't exist. Adding even more variants of clouds is confusing. If a way to shoo clouds around becomes available I will add it, but currently the code doesn't support this.
If there is a block that is not on the editor palette then it's because it's not a simple as clicking it into existence. If adding enemy ships at random become simple and definitely not the cause of a bug, I will add it.