GIMP is a bitmap app, not a vector programme. It has layers
Speaking from experience - although GIMP has features I can't reproduce in CC3, like the ability to variably blend one fill into another using a brush, it can only do so with a maximum of 7 layers at a time on my machine, whereas working on the very same machine in CC3 I can have at least 135 layers (CC3 sheets) in one file and still be working on it with all 350 sheet effects turned on. That is why I don't believe 32-bit software is necessarily inferior to 64-bit software.
There is simply no way that I could have created Merelan City in GIMP on my machine. GIMP might be a 64-bit app, but its just isn't efficient enough with the system memory and processing power to be able to do much more than a very small corner of the CC3 map I created.
The same is also true of all the other 64-bit graphics apps I have - CorelDraw 11, Corel Photopaint 11, Krita... and so on.