I have a friend who loves her Mr. Beer and the beer that comes out of it. She's happy with it, and there are others that are also.
Mr. Beer is easy to use, and that really is the point of it. It makes a drinkable beverage that is simple, and that is what makes her happy. For me, though, I don't think the beer is even of average quality and I don't like it so it didn't make me happy when I bought one. I don't mean to run down Mr. Beer- some people are happy with them and in a few weeks we'll have a ton of new brewers on this forum who received Mr. Beer for Christmas- but the quality of a beer is only as good as the ingredients going into.
I consider a "tier" of ingredients for beginners, sort of like this (compared to cooking):
Mr Beer/Beer Machine: Canned spaghetti sauce
Extract beer/hops made fresh: Jarred spaghetti sauce
Extract beer made with specialty grains or partial mash: homemade spaghetti sauce
When I was in college, canned Hunt's spaghetti sauce was just fine. Easy, cheap, and edible. That's how I think of Mr. Beer- it may be easy and drinkable and some people will be happy with that.
It sounds like you are disappointed in the quality of the Mr. Beer kits' ingredients. The size is a nice sized fermenter, so if you want to step it up a bit you can buy some extract, grains, hops, and yeast (we can help you with what you need, and how to do it), and use that fermenter from the Mr. Beer set up to make a much better beer when you are ready.