You know your "ROM Base"? The rule you put about "Can only use if progressed quite far" isn't the greatest rule. ROM Bases are a start point, and then are improved with the person's own talent. So, they need to use it to start off, otherwise they:
A - Will have to redo their work,which would be annoying,
B - Will have no need to use the ROM Base, as if they have progressed, they wouldn't ever need to use the ROM Base.
So, your Base isn't really helping people, as those who progress mostly know how to (and will have done at some point) insert tiles.