P.Bull, Y. Akrami, et al. "Beyond ΛCDM: Problems, solutions, and the road ahead" 77 pages + 517 references arXiv:1512.05356 Written not without humour: e.g. pg. 67: "As Tom Shanks once said, there are only two things wrong with ΛCDM: Λ and CDM." " ΛCDM is like Hotel California: it is very hard to leave, and most, if not all, efforts to do so have ended with some insurmountable obstacle." I'd like to recommend this paper for reading between the years for some discussions in 2016.