Look, it doesnt make sense. It will cost too much more, have very little to mine and be at the whim of the antminer E3 pricing basically lol.
Most important question. WHY just WHY do u wanna make an FPGA when one asic already controls 64% of GPU mining? A few asics control most of the GPU mining already.
And this FPGA u are doing is just another GPU. Why? Because anyone can do it. U make a slightly stronger GPU known as FPGA. All u need is abit of dumb money going in there and u make no profits due to high difficulty.
In my opinion, interest to FPGA can be short-term, when you need to mine a certain number of coins before the release of ASIC. Like a Groestl, Nist5 and others.
But a more fundamental interest may be to offer a useful proof of work function which can also be ASIC-resistant.
By setting new standards for the usefulness of the POW function, we will strengthen mining on FPGA in the long term.
In the end, someone uses mega-FPGA cards in real life. For what? Amazon AWS earns with them, why not do the same?