I wouldn't want to get rid of buy mode, at all. I've played games like Oblivion and Animal Crossing...It's not too fun arranging your house by shoving around furniture after running all the way across town to get it from the store keeper, nor is it fun to drag what little furniture you -can- move by yourself around a house, especially when it's something like a broom, and it knocks over absolutly everything you've done once you get it to the right position by the door. And then there was the 'suspended paintbrushes' that I put out, couldn't find, and promptly ran into.
If they were to get shops and such, maybe the shops could have better or unusual furniture/appliances/decorations, and maybe for cheaper than buy mode...Similar to a consignment shop. They could have sales like the bookstore and grocery store, and maybe you'd even have payment plans if you couldn't buy the furniture or appliance for full price, like real stores do. Finally, you couldn't loaf there like you can at a consignment shop or firehouse, because it'll close after a while, but you could break in as a theif and grab a few peices of free stuff before the cops show up.
I'd love for the school to get more involved, and after school activites do sound like fun, but they do already have opportunities for stuff like clubs or assigments. It would be nice if they got even better, though...Like needing to use a sculpting wheel or drawing board/easel to make a science project display, studying more classes that increased skills, writing a school paper or report every once in a while...It's too bad they didn't concider this with Ambitions.