Hello everyone, i could really use your help with this!

I have already poked around the internet and read up on several threads, but i still need help confirming whether what i imagine is actually possible or not..

My cube will be intended for kitchentable play with a few of my friends, so i figured that the smallest size of 360 cards is very suitable. However, i have learned that beginners are best off starting with a pauper cube (which for price reasons i eagerly accept as true). Now the source of confusion for me stems from the idea that theming cubes around specific blocks (which ive heard is a thing) is something very alluring to me. Because of my fondness for the flavour of the recent 'Shadows Over Innistrad' block, i am brought to wonder if it is actually possible to make a SOI Pauper Cube?

After reading into the composition of that block, and the fact that cube is strictly a singleton format, it has come to my attention that the block straight up lacks enough commons to make the 360 total needed. And that's not even before colour balancing is even considered! So if that is no longer possible i am happy to extend the reaches of my card pool to include the BFZ block as it shares the Eldrazi storyline (which is why i like SOI so much). But once again there aren't even enough commons if my math is correct. So at the very minimum it looks like i'm pushed into using Magic Origins as well?

Can someone look at this problem with fresh eyes? Am i doing something wrong here? Is this a dumb idea and i should quit or is it actually salvageable?

Thanks in advance!