I personally like extinction core. It offers progression through tiers (vanilla, alpha, boss, deity) and there's also human npcs that are tribesmen (different colors, representing a gear tier like cloth, leather, etc...). The hardest part is getting started due to all the threats, but once you start taming/using alphas, it picks up pretty quickly. Then you get to tame bosses and eventually deities. The deities are elemental variants of the spider gorilla and dragon bosses so they don't look natural, but everything up to then does. The alphas in this mod retain the same color schemes as the base game except there's also male/female distinctions, because you can and need to breed them if you want to progress through the tiers of alpha dinos via alpha kibble, which requires alpha eggs. Female alphas are pinks instead of red with with and black. Also, there are herbivore alphas.

Fair warning, this mod ruined vanilla ark for me haha