I have mined with a couple different cards and the 1070 felt smooth and hashed like a beast, but I couldn't justify the extra cost.
The 1050 and 1050ti are too low earnings per slot taken although I guess with the 12/13 slot mobos then maybe the cost of the system wont be in such bad ratio to it's earnings per gpu.
So that left me between the Radeon RX cards and the 1060. Which meant the GPU lottery is very important
Ultimately I preferred the 1060's because with samsung ram(normally in the mining cards with 3 month warranty) can get very close to the radeons in hash/w for Eth. But not cryptonite.
The major bonus is actually on some of the other algos like neoscrypt, zcash,skunk, c11 and 1 or 2 other algorithms that I havn't really mined with.
and for neoscrypt...the 1060 can actually almost match a 1070 in earnings 800-900kh vs 1-1.1Mh. But never had the chance to compare power efficiency between the 2

TLDR
Overall I felt the 1060 mining cards were the best value for money. That being said I should have 6-8 of those and RX cards in the next couple weeks(total 12-14 gpus). Because it's good to cover weaknesses and just point them at their favorite algorithms.