Could be successful. You need to be entertaining for the viewers. Think of yourself as the viewer. Would you want to watch your own gameplay?
Forget GTA V and AC4. Wait for the next big game like Titanfall, either pre-order it or wait in line a couple hours for it(this will probably be better), make your gameplay commentary, be one of the first to upload it to YouTube, rank it with good on page SEO, and buy some HR views, subs, likes, and comments to give your video a good kickstart. The kickstart will make your videos look "superior" in stats so viewers would be tempted to watch you video instead of the others. Good luck OP
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I would do this, but I really can't entertain anyone better than a dead horse xD
EDIT: OP, since you only have $50 to invest, I strongly suggest you commentate a PC game, like Titanfall. You can easily get a screen capture software like Camtasia for free (search it up on YouTube), and use that money to buy the game. Hope my post was helpful to you