FPGA board for substituting microcontrollers

Hi,

I'd like an FPGA board which is a good platform for 32bit SoftCore microcontrollers.
Some of the key points:
- real USB connection (not USB to serial) with on-board connector, free IP and firmware is available for creating custom USB protocols (EndPoint managament, packet based communication, etc., similar to XMOS's USB lib)
- can be programmed over USB (both the FPGA and the SoftCore's code flash) with on-board connector
- powering over USB is an advantage
- 2 piece of external SRAM with 32 bit data bus and at least 16bit address bus: one is for tightly attached data memory of the SoftCore CPU, the other one is for shared memory (arbitrated among more bus masters, like SoftCore CPU, and custom logic)
- 1 parallel flash with 32 bit data bus and at least 16bit address bus, it would be the tightly attached code memory of the SoftCore CPU
- just enough GPIOs (>=64) connected to hobbiest friendly headers (no PCIe and similar headers)
- FreeRTOS should be available for the SoftCore CPU
- free and good development tools on Linux

Currently I'd prefer some Altera based solution, because:
- I have briefly read about Nios2 and that just seems to be good
- I have heard that the dev tool (Quartus) works well on Linux and that is somewhat better and simpler than Xilinx tools and a bit lighter weight

I have spent many time finding a similar board but I have found nothing. Boards what I have found are too simple or too complicated.

Any idea or suggestion?

Thanks!

As an alternative, is there a board which doesn't have the required external SRAM and parallel flash configuraion, but its FPGA has at least 512kByte internal Block RAM and it hasn't got planetary price?