I don't think it'd be boring...that is, unless you automatically had access to everything without even buying anything. If you just mean trading wouldn't be such a huge deal, then it's a great idea.
I was on an MMO years ago called Muichiz. It used Activeworlds; you bought a handheld game and connected it to your computer via a usb port. There was no trading, and the game was great. There was no "rare" and the game was great... And there were only 4 "worlds" to be honest. You automatically had access to one world depending on what your character was. (The other "world" was the main one -- where you landed when you logged in. You automatically had access to it too. It had stores, a bank, a hotel -- I think you could rent rooms but I never tried, etc...) You could buy temporary access to the others (it was basically a passport).
People spent most of their time playing games or just chatting together. I think there were approximately 2-4 games per world, so there was plenty to do. There was no magic, but you could use movers (they were essentially cars. Some were like motorcyles or something though). You earned credits through the games.. You spent them on clothes, hair, hats, houses, or food (you had to make sure your character was well feed and happy).
If someone wants to attempt to revive Muichiz, I'd be all up for xD.
Anyway, the point is, trading doesn't have to be such an integral part of a game. It only is if the players (and the staff) let it become that way. Too much trading ruins an economy. Pretty much everyone had access to everything Muichiz... It was your choice whether you bought it or not, so nothing was rare.