For the first word all the variants have a negative connotation. At the moment I can't find a good neutral variant for that. We don't say like that. If we say "shameless" it's always negative. A person who communicates without problem is коммуникабельный/общительный/контактный человек.

For the second one:
Успешный предприниматель, преуспевающий бизнесмен are perfect.
Удачный refers to "lucky" or "successful" like in "successful attempt", удачливый also refers to "lucky": He is a lucky investor = Он удачливый (= везучий) инвестор.