Learn English – Noun for “a person who deeply appreciates aesthetics”

Consider the term aficionado (“A person who likes, knows about, and appreciates a particular interest or activity; a fan or devotee”), for use in a phrase like “She's an aficionado of life.” I don't know of an adjectival form.

The verb savor (“to appreciate, enjoy or relish something”) is relevant, eg “She savors life.” Again, I don't know of an adjectival form.

The adjective appreciative (“Showing appreciation or gratitude”) may apply, but is somewhat nondescript and general. Optimistic, positive, and upbeat (“Having a positive, lively, or perky tone, attitude, etc.”), are perhaps more relevant; a sentence like “Sally's an upbeat person” implies Sally is an active person, appreciative of life, has positive attitude, etc.

The adjectives epicurean (“pursuing pleasure, especially in reference to food or comfort”) and hedonistic (“Devoted to pleasure; epicurean”) may apply but are slightly pejorative. (Note, hedonistic is antonymic to ascetic (“...characterized by rigorous self-denial or self-discipline; austere; abstinent; involving a withholding of physical pleasure”).)

The word that springs to mind for me is "completionist." I initially began using the word in reference to MMO (Massively Multi-player Online) gamers who sought to collect every "achievement."

I have since heard the word used to describe gamers who desire 100% completion of any particular aspect of a game. Examples range from in game achievements, to clothing, quests, or 100% completion status.

Wiktionary defines the word as follows:

Completionist - one who insists on completion.

This urban dictionary listing from 2010 more closely matches the usage I am familiar with as a native North American English speaker and online gamer:

Completionist - Someone who, when playing a video game, has to collect all of a certain item, or complete something in the game 100%.

"Only a completionist would collect all of the flags in Assassin's Creed."