There are countless ways.
You can combine them as a bigger texture natively:
1 - You can shuffle your texture like you're doing right now;
2 - Select all faces and edges (by triple clicking on one of them) for instance;
3 - Then right click on one of the selected faces;
4 - Use soften/smooth;
5 - Soften everything and check the soften coplanar check box;
6 - Now all faces are a surface
7 - Rightclick on the surface (be carefull to have hidden edges turned off) and it selects all faces at the same time
8 - On that context menu choose make unique texture. It will generate a new texture 2048x2048px or 4096x4096px depending on the texture resolution you have set on preferences.
There are plugins that shuffle texture position on faces. Try some of the following plugins and then investigate about UV mapping and search for UV in the Sketchucation Store.
http://sketchucation.com/pluginstore?pln=ene_texturepositioning_v1.0.2_0
http://sketchucation.com/pluginstore?pln=TextureRandomizer
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