Informal survey: room for improvement

Where do you think your/our bidding could be better? I posted the Jacoby 2NT and Roman Key Card Blackwood conventions to help with finding slam contracts (still a little ways to go there), and we've been working on our Stayman, but there are still vast untapped areas.

What bidding moments do you find too ambiguous or difficult to communicate about? What contracts do you consistently have trouble landing in? What are you always wishing you could whisper to your partner?