First, I like your motivation to improve FGPA mining and don't want to frustrate you.

Just let me give you my feedback.

I'm quite sure that the Cyclone V will not be available for your project in the middle of the year.
Indeed the new 28nm FPGA's are quit interesting for mining, but it's expected that Xilinx will first get out with their Artix-7 before Altera can do with their Cyclone V.
They start the whole 28nm process-change far before Altera, and they have the very first 28nm FPGAs (e.g. Kintex-7 and Zynq) in small amounts 'available'.

And eveything looks like the new Xilinx chips (Artix-7) will not be available before at least 6-8 month, so I would not count on available Cyclone V chips before end of this year.

Current: Altera Cyclone IV vs. Xilinx Spartan-6
New: Altera Cyclone V vs. Xilinx Artix-7

Even if both new comparable FPGA series are available, we know from the current designs that the Xilinx FPGA's are more interesting for mining. Everything looks like this will also be the case with the new series.
You made very interesting announcements, that you think you will be able to squeeze out more MH/s on Cyclone IV chips (+75MH/s on a DE0 nano). How close did you already reach your expectations and who much hope did you still have to squeeze out more?  

I would wait until it is more likely that the new interesting 28nm Chips will be available soon and then think again if it still makes sense to start a project with them.

If you still have good ideas how to optimize the existing FPGA logic for mining, you can do it right away. With every new FPGA-miner the market for optimization growth.