Eliminate 30% of the parts from any design
Time and time again very large companies design sub-assemblies and are not very careful about how they design them. Engineering teams are leaving big money on the table and leaving it to the supply chain group to get the costs under control.
It doesn't have to be this way.
Here are some extremely common things I see when performing design optimization:
Custom brackets. All too often a series of little Sheetmetal bits are put in place to hold everything together and in place. There are tons of bracket and support products commercially available such as Unistrut.
Over-specialization of parts. A string of parts will have a switch, a meter, and a signaling device. There are a huge number of products that combine several functions into a single part. Furthermore a piece of sheet metal can be folded a limitless number of ways and outfitted with a massive amount of retention and support features.
Use of adapter fittings or elbows. When adapting from x to z often adapters are readily available that go x to y and y to z. Look a little harder and you'll find the adapter that goes from x to z. Consider calling a supplier like Swagelok, they have parts that aren't listed online or in the catalog that go from x to z. Why do with fittings when you can do it with a pipe/tube bender? More bends people. More bends.
Follow these rules and you'll put yourself far ahead of your competition in price and performance.