Since I opened an art shop, I've been using the trading feature a lot. And one thing I've noticed is that I absolutely hate how overly complicated it is. Why do we need so many instances of accepting?
I personally think that taking out the 'do you wish to have a trade with this user' thing would be ideal. Just post your offer to the person, and it immediately goes through. Then the receiving party can choose to accept, post their own offer, or deny. Then the original person can accept after viewing the other person's response, if they didn't cancel.

i also only get notified when i get a trade request or when someone accepts my request. no notifications when items are added or the offer is accepted so it's easy to forget about.