Good idea! It should be in a format that fits to the thumbnails at steemit.com so that it looks good there.
I thought about a competition to design a logo, but I prefer a very easy one so that it is visible as thumbnail too. And we need 2 logos: one for normal chess and one for 960. The date inside the logo is too much work for every week. I will pay 10 SBD for the best logo. I will make a post about it soon. Feel free to make your own reminder post with your logo, all payout is for you!