Sometimes simple really is what you need, and this could fit you well.
Source Factorio.us Collective
Prismatic Floral Background No Black
Source GDJ
Tiny, tiny 3D cubes. Reminds me of the good old pattern from k10k.
Source Etienne Rallion
Prismatic Geometric Pattern Background 2
Source GDJ
And some more testing, this time with Seamless Studio. It’s Robots FFS!
Source Seamless Studio
A seamless pattern from a tile made from a jpg on Pixabay. To get the tile select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zerro CC tillable texture of stones photographed and made by me. CC0
Source Sojan Janso
High detail stone wall with minor cracks and specks.
Source Projecteightyfive
From a tile that can be had by selecting the rectangle in Inkscape and using shift+alt+i.
Source Firkin
A version without colours blended together to give a different look.
Source Firkin
Here's a bluish gray striped background pattern for use on web sites.
Source V. Hartikainen
Here's an yet another background for websites, with a seamless texture of wood planks this time.
Source V. Hartikainen
A background pattern with a look of rough fabric.
Source V. Hartikainen
Prismatic Isometric Cube Extra Pattern No Background
Source GDJ
A bit like smudged paint or some sort of steel, here is scribble light.
Source Tegan Male
Simple wide squares with a small indent. Fits all.
Source Petr Šulc.
From a drawing in 'Navigations de Alouys de Cademoste.-La Navigation du Capitaine Pierre Sintre', Alvise da ca da Mosto, 1895.
Source Firkin
Bumps, highlight and shadows – all good things.
Source Badhon Ebrahim
Can never have too many knitting patterns, especially as nice as this.
Source Victoria Spahn
Brushed aluminum, in a bright gray version. Lovely 2X as well.
Source Andre Schouten
The image depicts a tiled seamless pattern.The tile represents four leaves aligned every 90 ° , which may look like a bird or a dragon .The original leaf design is from a Japanese old book.
Source Yamachem
Utilising some flowers from Almeidah. To get the unit tile, select the rectangle in Inkscape and use shift-alt-i.
Source Firkin