Starting a sentence with "being" is perfectly correct, as long as you're using the gerund. (Or the noun "being" as in "a celestial being.") Gerunds are verbs (or rather verb phrases) that became nouns (err...noun phrases), so they function just like any other noun. That includes being the subject of a sentence. Being the subject of a sentence is okay if it's a gerund. (See?)
Other examples with different kinds of descriptors and verbs:
"Being with you is eye-opening."
"Being right all the time is exhausting."
"Being powerful brings problems, too."
"Being sick means being tired."