I'd watch it every once in a while if it is the same game. A part of streaming is to be entertaining to the audience, which while your play is off the carts great, I don't think that watching the same game and play for days would be that great. Unless you get other people and friends, or something like that to make things interesting, or if there is hype for a match you plan on doing. But if you do a variety of games, even if just on some occasions, i'd defiantly watch those because i wouldn't know if you would play it again, but smash, if i ever have a craving to watch some, i'd know that when you're streaming, it's probably smash, so you'd be a big source for that, being who you are. But this is just my opinion.
Ultimately, it is all up to you and how you want to do it. You should try different things, streaming wise, to find out what it is you'd like to do, and if you want to sacrifice any of that, if anything, to compromise for more viewers.
Rule of thumb: Ask yourself if you'd want to watch that.