Why thank ye for the plug . Coming from you I take that as rather high praise
Since we are in disclaimer mode here: I too have never laid out silicon. I do not know or care to know the actual hardwired logic pathways in mining ASIC's. I do know more than a thing or 2 about high speed circuitry and the care/feeding thereof... My first experience with high-speed circuit layout originally comes from working with/building microwave coms gear in the early 1970's. Thing is, with the logic switching speeds ASIC's use all the same rules apply regarding local power decoupling and signal integrity vs the path routing. It is not only clock speed that gets you. More problematic is the rise/fall times of the signals inducing high levels of very localized odd-harmonics into the power plane and data signals.
Anywho, for the past 39 years my biz has been designing/building from framework to the control boards equipment used in some rather critical steps in chip fab processes. We build bleeding edge tech that makes making bleeding edge chips possible. That in turn is where my contacts with the semiconductor bix comes from. Natural curiosity and the need to know about all steps and I mean all involved is what keeps me current on what node-sizes the various major foundries can produce;) As for my blasting pre-packaged IP blocks a foundry or chip design house can provide, it is a common sense item any decent chip designer should follow if the goal is Best-in-Class. Far more risky yes because simulate all you want, until it is physically produced there is no third-party assurance (someone else to blame) that each function block actually does what it should.
If you want a 'safe' moderate performance first run chip as proof of concept, then use pre-packaged IP function blocks. They are proven to work and just need to be placed best as possible in the die and linked together anyway ya can. *That* is along the line of what that chip design site mentioned earlier on sounds like they do. At the more mature 22nm and higher nodes foundries can often provide short-runs by using 'spare' space on wafers to make more money per-wafer on what is often razor-thin margins from generic chips made on the same wafers. I rather doubt that 'low cost' option is yet available at 16/14nm. Scrap rate is still too high
As for hashing ASIC's themselves I highly recommend reading through the A1 chip dev thread starting here.
https://bitcointalk.org/index.php?topic=294235.360. I dived in there due to my ordering on of the ill-fated AMT/Bitmine.ch A1 based miners in Feb. 2014. It is a good read on the trial and tribulations of giving birth to a new miner design. Also points to, hell, screams where Bitmine.ch went so very wrong with their boards...
Enough of the mutual admiration club and back to the Topic. To the OP I say, if you think you have a core team that can do it then go for it. The mining community needs hardware choices. Just fully research what is going to be involved and round up (fully informed of the risks) investors. Again, I highly recommend that A1 dev thread for insite on what to expect.