I think the trading system is poor in G&K (have no idea if it will be improved in BNW). I believe most players to be like you, and simply do not use it, as it is almost never required for game victory.So tell me you actually enjoy having to dick around in the trade screen and do it all manually several hundred times a game... like I said, after years and billions of manual clicks later, I'm so freakin' tired of that crap. Automation is a very, very, verrrrrry good thing, sometimes.
The problem can be solved with a mod though, if Firaxes doesn't fix it in BNW. And it's a mod I've had my eye on for a long time. It's just a very complicated mod so it's been put off.
Unless you are dead set against mods, CivUp/Gem actually does some good work on making the system more usable by making the F2 screen interactive. And Whoward has a useful standalone but not as interactive version (the original) you can look at: here.