I've tested to stream a couple of times today, and my ping is going up to 150 on Discord.
My internet speed is 10mb/s download and 1mb/s upload.
I've watched Youtube videos on people saying to start at 2500 bitrate, but I decided to lower it. I've done that multiple times from 2500, so now it's at 1000 bitrate and still doing it.
I don't want to go too low, because I don't know how much bitrate is a good quality on the stream.
Best Answer
I'm in the same case as you (1Mb Upload) so I'm speaking from experience here.
It's hard to stream at that speed. I've blocked my bitrate to 800 for a 480p output image.
Still, if I do a fast movement (like spinning the camera around the character), it gets blurry.
On top of that, multiplayer has lots of lag spikes (tried with Dark Souls 3 which is peer to peer, could be different with a dedicated server game).
What I would advise is either :
To end on a more positive point, even if your stream is blurry, when Twitch transforms it into a VOD, it gets a little bit nicer / some of the blurryness goes away.