Maybe 1 diamond for a 64x64 IC is fine, but for a simple 16x16 one?! It must be around 16 times cheaper!
However, I don't think that it is a good idea to add "low-tech empty chips" that will, for example, use silicon instead of diamond and only allow up to 32x32 circuits. I'd rather think that 16x16 IC uses a smaller die than that it actually uses lower tech.

Also, I don't think that it makes sense to first make an IC, complete with IO pins, and only then print circuity on it, not the least because IO depends on blueprint used for printing.

For the 2 above reasons (and for "realism"), my suggestion:

• Replace "empty circuits" with wafers that are cooked or otherwise produced from diamonds and silicon. I think 1 diamond per wafer should be fine.
• Instead of having gold in "empty circuit" recipe, add it to IO component cost.
• IC fabrication process will consume the whole wafer in one go and produce several dies from the same blueprint. It should definitely be 1 die for 4x4 blueprint (I mean size in 16x16 blocks), 2 dies for 4x3 (to make this size be actually be worth using), 3 for 3x3, and, assuming smallest round wafer for the above 3 cases (8 blocks in diameter if I am right), as much smaller dies as will fit (it will be 41 dies for 1x1 blueprint if I am right).
• These dies are individually packed into IC gates. Same as now.

Well, maybe 41 identical ICs in one go is a bit overkill. Maybe add smaller wafers that will require less diamonds but will be less efficient. That is, same surface area for 1 diamond, but several round wafers instead of one, and so less circuits fit on them. Example: 1 diamond for 4-pack of wafers, each 4 blocks in diameter and allowing for 1 2x3 circuit or 8 1x1 circuits. Mass production for the win!

Or maybe process multiple blueprints in one go, allowing to specify amount for each and automatically packing them on wafer if possible. However, this will require some actual coding, unlike everything else suggested above.

Also, IMHO showing IC gate as chip with animated surface inside a glass box is totally unrealistic, although I agree that it looks cool :-) Make it be just a square with fancy animated "wires" if you really want a glass box. IMHO of course.

Edit: after discussion in #911, I no longer think it is a good idea. Having just different tiers of "raw chips" is much more sensible if you don't think of blueprint as a physical die layout.