: RE: Brothers, many of the characters I've never heard anyone use. Are they usually only written or used in special situations? Ge-ge (pinyin) seems to be missing is this only spoken?
in fact, they are a bit common when naming one's children. for instance, you may find someone's name called baak3, zung6, suk1 or gwai3(all in cantonese). it shows that their parents'/families' respect for seniority. so they named their sons in order (zhang3you4you3xu4 or zoeng2jau3jau5zeoi6). and i don't think it as an special situation, this is chinese tradition
you are right. ge1-ge also means elder brother. and it is not only for spoken you may write it down as well. but the one i mentioned is much more formal than ge1 especially when you are to write it down.
: The 3rd character you have for elder brother, I thought meant uncle (paternal uncle older than father) and is pronounced bak in Cantonese.
you are 50% correct:( baak3 is in fact used for the eldest brother. and for the paternal uncle elder than one's father should be called "baak3(eldest brother -of) fu6(father)" in full. baak3 is just a short form of addressing you paternal uncle elder than one's father. same to "suk1" for the paternal uncle younger than one's father. in full you should called the paternal uncle younger than your father as "suk1(younger brother-of) fu6(father)"
hope this helps