My suggestion is to use the DE-Nano board. At $90.00 on Digikey, this price is very competitive. The parts alone on Digikey would put you in the $150 to $200 range. The Cyclone IV part on this board has 66 embedded multipliers and 38K of 16bit wide RAM available. There are three expansion headers, located on three different edges of the board, for easy access. My thought would be to put your analog and pushbuttons on an expander card and connect via ribbon cable to one of the 2x40 row headers on the DE-Nano. The great thing is that this part is available in TQFP so if you wanted to make your own version of this board you could do a 1:1 compatibility with this part. Best, James