Needs more originality
I applaud your ability to create a game. The art was nearly flawless, and the gameplay was good.
The problem is, the art and the gameplay (even the level design, character select, etc) were copied almost completely from Super Mario Brothers 2, NES. I understand it's a homage, but that doesn't mean it needs to be identical. There was plenty of room for more originality, especially on the art side of things. I played through the first section and it brought back memories, which is why you get a 7. But it didn't deliver anything new. With a name like Super Mafia Brothers (which is clever), I at least expected to see some sort of gameplay mechanic or art design that would stray from the original Mario Brothers to deliver something new and creative. Instead I got the same thing I could play on my NES emulator. I think it shows your potential as 2D game makers/animators/designers, but definetely work on your originality.
Overall, good job, though. Fun. Although a bit laggy, and my computer usually handles these things pretty well. In fact it always does. So I'm wondering if it's me.