Hi Escuan,
16a - old, obscure word for "cracked". Anagram of two letters of try, plus a common two-letter abbreviation for 4, and abbreviation for down
16d - this one is thematic, but for the "original" answer, think four-letter word for girl in a well-known three-letter word revolutionary, dropping a letter, with an s. Definition is lectures.
30a - first three words are definition. Nurse is TEND.
21 - think the last bit bit of a cigarette
22 - thematic clue, but "original" answer" is a two-letter abbreviation for gold inside a five-letter word (losing a letter) that begins with F.
Really tough this one. I still can't parse 20d or 28d (not looking for hints, but it's just annoying me).