Colour cubes

I started to add colour to one of the cube designs to see how it could be used as a brand over a range of products and material and come together as a range. I tried out a random few colours. Some like the yellow don't let the white work properly and it isn't very legible.

Then I attempted to make a block of them placing them ontop and next to each other so I could create shapes with it. Unfortunately I haven't designed the cubes perfectly so they aren't correct cubes but as first idea I like the idea of blocking them together and think I could play around with this.

The type is placed too close to the top edge so when they are placed on top they almost overlap the type.

I also think the colours look too childish and could represnt childrens building blocks so I might have to stay clear of colour of ensure I choose a suitable colour palette.