I'd be happy enough with floating sheets. To resolve those common things where you've got two different sections, like an analysis with a summary section below

I'd be happy enough with floating sheets. To resolve those common things where you've got two different sections, like an analysis with a summary section below it. It's annoying because e.g. changing the column width on the top part also changes the column width on the independent thing below it. A tool that lets me put multiple independent sheets on the same page would be great. If the tool can be programmed to run image processing algorithms on the same page, that's fine too. I'd view "IO" as almost equivalent to "Macro" in that instance. Though not quite. I'd like to be able to have e.g. $A$1 be a filename and $A$2 be the image in file $A$1, and that to be understood as a "pure" transform, even though under the hood it's got to open the file. So "application-scope purity" rather than process-scope purity.