What's wrong with Modnation Racers

About a month ago I decided to finally spend my money and buy Modnation Racers. I loved making tracks in the demo and thought the racing was better than other kart racers, and most of all I had fun with what little the demo offered. The first week I played Modnation, I loved it. I didn't really care about the horrendous load times, as long as I got to do what I wanted to do. And after a week of having fun with it, I took a break with it to play through Red Dead Redemption. A couple weeks later I came back to Modnation, and I found out had flawed it really is. I tried playing through the rest of the career, which I didn't finish, so I could unlock everything, and then make my tracks with everything unlocked. But I can't, because the difficulty and cheating AI make this game totally unfun, which is the opposite of what a kart racer should be. And once you start getting frustrated you realize how long it takes to get from one thing to the next. And I can't have fun just making tracks, when half of all the cool objects are locked unless I beat those infuriating challenges in the career mode. I've been reading on the PS Blog that United Front Games (the devs) are working on a patch to fix the unacceptable load times and a new casual mode that makes the career slightly easier, and if they ever get it out, I will definitely go back to Modnation Racers, but until this game gets patched, it's staying right on my shelf while I play something more exciting.