Chomping Changeling and Masked Vandal are great cards for every Tribal build as they combine artifact/enchantment removal on ETB with Tribal synergy
A lot of the best beasts aren't legendary, so Reflections of Littjara is another good choice
One of these will be shockingly good in Standard, to my chagrin, but Ive got serious doubts about some seemingly popular cards like: Dragonhawk, Fate's Tempest Eluge, the Shoreless Sea Glarb, Calamity's Augur Helga, Skittish Seer Hugs, Grisly Guardian Mabel, Heir to Cragflame Muerra, Trash Tactician Vren, the Relentless Wick, the Whorled Mind So yeah, most of the story arc cast is underwhelming
The Rest There are some ramp cards that dont quite fit the other categories, but deserve a mention nonetheless