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Everyone I know that has tried to cover all these bases have anded up with something unwieldy that was found not to cover the next project. A devel opment board is not a universal board, to make that, you would, in addition to what you mention need to add A/d D/A linear to 4-20, LED and LCD display, optocouplers, 485, 232, IBIS, J1708, IIC and SPI interfaces and a whole lot more. As Robert Storm Petersen said "it is difficult to predict, especially the future".

The "universal board" is an unattainable goal, a simple development board, possibly with a lot of solder pad area is reasonable.

Two issues:
1) DO NOT include the stupid 8255
2) As other posters have mentioned KISS (keep it simple, stupid)

Erik