Should we use the new CAESAR competition ciphers?
The CAESAR competition took way too long, didn't go as well as expected, and other interesting constructions that would have been worth considering were designed after it started.

Some of these (AES-GCM-SIV) got standardized before the competition was over, and may get more adoption than CAESAR candidates.

The goal of CAESAR wasn't clearly defined. We didn't end up with AES alternatives. If only because AES is well-supported in hardware and has no sign of being broken anytime soon.

I'm not convinced of the practical outcome of the NIST LWCC competition either. AES is here to stay.

To get back to CAESAR, some finalists are interesting.

In particular, AEGIS doesn't change the AES core function, but builds a very fast (faster than AES-GCM) and simple construction taking advantage of the parallelism of some CPUs. 

AEGIS-256 has been implemented in libsodium. So, it may get some adoption for applications where speed is the primary concern.