The 'problem' with making a logo with colored blocks in SM is that this is only possible for large to huge ships. For smaller ones only a very simple design is doable and even then there will be logo design restrictions with the building of your craft.
Another possibility is to have a look at text based art that can be done using display blocks. This gives a lot of options, less restrictions in logo design, and is certainly usable for smaller ships. It will be a lot of work to implement, but certainly worth a try. Have look
here for a intro video and a link to a blueprint to get you started.
Greets,
Jan