Depends on the functions and you really. If they are high social then it might be frowned upon, but most people are accepting that not everyone has eveningwear.
Why a waistcoat? Never worn one myself. For the love of all things please wear a ‘normal’ collar. Wing collars are for white tie and gits.
For male eveningwear, the question should always be ‘What would James Bond wear’? Black, proper collar.
Shoes need to be black and well polished. Crap shoes will always drag a man down.