Colorful Stripes Background #400
 Noise  CC 0

Colorful Stripes Background

Source GDJ

 More Textures
Fabric pattern (colour 2) #2401
 Fabric  CC 0

Alternative colour scheme. Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Fabric pattern 2 (colour 6) #2391
 Fabric  CC 0

Not a pattern for fabrics, but one produced from a jpg of a stack of fabric items that was posted on Pixabay. The tile that this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i.

Source Firkin

Prismatic Snowflakes Pattern No Background #411
 Light  CC 0

Prismatic Snowflakes Pattern No Background

Source GDJ

Prismatic Abstract Background Design #403
 Noise  CC 0

Prismatic Abstract Background Design

Source GDJ

Batthern #324
 Grid  CC BY-SA 3.0

Sometimes simple really is what you need, and this could fit you well.

Source Factorio.us Collective

Background pattern 225 (colour 5) #2323
 Blue  CC 0

Seamless pattern formed from a tile that can be extracted by selecting the rectangle in Inkscape and using shift-alt-i.

Source Firkin

Colorful Bicycles Background #207
 Noise  CC 0

Pixabay.

Source GDJ

Polonez Pattern@2X #335
 Gray  CC BY-SA 3.0

A car pattern?! Can it be subtle? I say yes!

Source Radosław Rzepecki

Floral pattern 14 #1754
 Yellow  CC 0

The tile this is based on can be had by selecting the rectangle in Inkscape and using shift+alt+i

Source Firkin

Abstract Arbitrary Geometric Background #497
 Noise  CC 0

Abstract Arbitrary Geometric Background derived from an image on Pixabay.

Source GDJ

Noisy@2X #46
 Paper  CC BY-SA 3.0

Looks a bit like concrete with subtle specks spread around the pattern.

Source Mladjan Antic