More websites mean more visibility. Even if it only an extra two people.
When you get a contract offered: for fucks sake READ THE DAMN THING. That is all.
Also, get an agent. I got my two offers first, then approached an agent, which also got me a discount as I had removed some of the work and a lot of the risk. To be clear: that's a smaller percentage/commission. Agents are *NEVER* paid up front/hourly, which is also why they can be picky. Any 'agent' who asked for anything other than a commission is trying to scam you.
I told him what my priorities were on the contract, which included ensuring that *all* rights revert to me should they choose to stop publishing my work for a sufficiently long period, along with some other changes regarding specific rights. He got me what was most important to me.
Note: the agent is your advocate in all things, which is part of the reason for the percentage. I had some issues with the cover art, I talked with my agent, he pushed on my behalf and got some modifications, then told me he thought we should hold there rather than push more. Gives us a better reputation and better standing if we need to push back on something else in the future.