Exposed Parameter version of Tile Sampler not using all 6 Pattern Inputs.

I'm trying to create a tile generator for my team, and have therefore created a base graph setup with a lot of exposed parameters that users can then input into their own graphs to blend tile and grout materials. 

I'm using tile sampler as we require a lot of pattern imputs, but for some reason my "TileBaseGraph" node that I have created only uses the first pattern imput, even when 6 different patterns are plugged in. I've tested the patterns with a simple Tile Sampler node and its working fine, so it's definitely something to do with the way I've set up my base graph. 

Rather than waffle trying to explain everything here I've attached a version of the file, with annotations.

If someone with better knowledge on creating procedural graphs and exposing parameters and inputs could take a look and help me out I'd be forever grateful!