TL;DR
Create ghost for cursor while crafting by hand, replace by entity when crafted.What ?
When crafting an entity from the crafting menu the cursor should become a ghost of that entity. When the entity is added to the inventory (or one already exists) the cursor should change to the entity.Why ?
Often while building one runs out of something, e.g. chemical plants. So one has to open the crafting menu, find the chemical plant and craft one. Then one has to wait till the chemical plant is crafted, open the inventory, find the chemical plant, select it, close the inventory and place it. This is time consuming and annoying.For more frequent entities one can add them to the quickbar and select them from there. With the right option one then gets a ghost of the entity in the cursor and can place ghosts while it is still crafting. This saves a lot of time and with personal construction bots or mods like bluebuild it is close to building the entity directly. So there is precedence for creating ghost cursors but the Quickbar is too limited and still means one has to find the entity being crafted in the Quickbar first.
When crafting something it is highly likely the entity will be placed on the map next. Putting that entity into the cursor automatically would save a lot of mouse movement and clicks. Turning the ghost cursor into a real entity cursor once the crafting is finished would simplify placing entities before personal construction bots or without mods like bluebuild. It would also be helpful for the rarer cases that one hand crafts item to place into an assembler or chest. It would become as simple as craft, wait for crafting to finish, ctrl-click to transfer cursor to assembler or chest.
Overall I can't see any case where putting the item being crafted into the cursor would be harmful while it is often highly desirable.
