Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
From a drawing in 'Sun Pictures of the Norfolk Broads', Ernest Suffling, 1892.
Source Firkin
The image depicts a seamless pattern which includes hexagonally-aligned gourds with BG in light-brown.
Source Yamachem
Bright Multicolored Floral Background by Karen Arnold from PDP.
Source GDJ
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Remixed from an image that was uploaded to Pixabay by Pixeline
Source Firkin
A nice one indeed, but I have a feeling we have it already? If you spot a copy, let me know on Twitter.
Source Graphiste
This is a remix of "geometrical pattern 01".
Source Yamachem
The image depicts a seamless pattern of pine tree leaves.
Source Yamachem
Fix and cc0 to get the tile this is based on.
Source SliverKnight
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
A free web background image with a seamless concrete-like texture and an Indian-red color.
Source V. Hartikainen
The tile this is based on can be retrieved by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
Prismatic Groovy Concentric Background 2
Source GDJ
Remixed from a drawing in 'Chambéry à la fin du XIVe siècle', Timoleon Chapperon, 1863.
Source Firkin
Prismatic Curved Diamond Pattern No Background
Source GDJ
One more brick pattern. A bit more depth to this one.
Source Benjamin Ward
Pattern #100! A black classic knit-looking pattern.
Source Factorio.us Collective
Some more diagonal lines and noise, because you know you want it.
Source Atle Mo
I have no idea what J Boo means by this name, but hey – it’s hot.
Source j Boo