TCP/NC = network coding I assume. This is not really a competitor to PCC: the two techniques are solving different problems and could work together. PCC controls the sending rate, while erasure coding (in general - I'm not familiar with the details of TCP/NC) avoids extra round trips to recover from losses. Erasure coding would be quite relevant to very short flows, for which every RTT matters, which is extremely interesting and valuable but not the focus of this paper. Also note TCP/NC needs a new end-to-end protocol.
CTCP is probably compound TCP. We haven't done a performance comparison but it appears to fall within the large set of TCP variants that use what we called "hardwired" control. If you try it out, let us know!
1. RCP 2. XCP 3. TCP CUBIC 4. FAST TCP 5. Remy
Not being in this area it is hard to know if TCP/NC and CTCP are important protocols which should have been included in the evaluation or if they even solve the same problem.