Is it all loops, or have you used any software instruments in there?
Your brother is right, it is too long and loopy, but… For the kind of sound you’ve gone for here, you could easily make it into a still rather long track (say 8 mins or so) without it ever feeling like it gets repetitive.
Where have you got all your samples from?
Mixing wise, your bass is too muddy, and you’ve probably not got enough excitement in the mid-highs to the highs. Which to be fair, is the same mistakes everyone makes at their first attempts, so don’t worry about that. Do you use any kind of spectrum/frequency analyser at all? I’m not familiar with Ableton, but Logic has one built in which is very useful for helping you watch the frequencies.
Overall though, for a first effort, even if everything is just loops, based on the song structure and the fact you’ve got everything working quite well together in the mix, a solid 8/10 from me…
I’ve clicked to follow you on soundcloud, add me…