 iSquared-C lets you connect many devices with low pin count, and with Stem-AQ-T you can even chain boards, but it can hit limits when operating over distances of a meter plus. Increasing a wire's length also increases its capacitance, which can cause your waveform to rise slowly, and inductance which can add ringing to the signal. So sending iSquared-C lines over multiple meters may leave your signals looking pretty rough. If long distance is a must, you can try lowering the clock speed to say 50 or 10 kHz, which can give the bus extra time to propagate over long wires. iSquared-C has no minimum clock speed, so worth a try? Or you can maintain speed with support hardware, like the LTC4311 active terminator. This chip injects a current boost whenever it senses the bus's pull-up resistors in use, dramatically improving rise time for each bit of data.