If you have a long expression, you can break it into multiple ones by storing some intermediate results in another cell. You can also hide such cells or put them in another sheet.

This might sound like a hack, but being able to see intermediate results makes debugging complex expressions easier too, so in a sense it is working as intended.

Formula -> Trace Dependencies/Precedents is also super handy! I have a short VBA loop that applies it to all selected cells. It makes it very easy to visually spot one cell reference that's wrong, because 20 cells connect to corresponding cells with parallel lines, then one isn't parallel.

Ctrl+Tilda toggles show/hide formulas, which helps identify input cells when you inherit a messy spreadsheet.

3D Excel would be intriguing. A dimension on which to store intermediate calculations.

Sounds like https://en.wikipedia.org/wiki/Lotus_Improv

I would love just getting the ability to resize the Evaluate Formula dialogue box text area.

The most painful thing for me, but not to ordinary users, is that the formulas are localized in the user's language.

This is a big one, especially if your edition isn't English/US.

Also the number formats and locale settings can cause quite a bit of trouble, if its not English/US. Alot of data warehouse setups output files with U.S formats even in Europe.

+1 The devil has many names. VLOOKUP and SVERWEIS (German) are two of them.

On longer formulas, I do Alt+Enter while editing the formula to get a new line, then 4 spaces for an indentation. Just like that, you can keep track of start/end parenthesis.

It's not perfect, I wish it would automatically format that way, but it certainly makes maintenance easier.

The new Let() function gives you multi row formulas, with local variables.

https://insider.office.com/en-us/blog/let-names-in-formulas-...

And it's a hack, but you can put text comments inside an N() function and add them into your formulas.

https://support.microsoft.com/en-us/office/n-function-a624ca...

You can put the comments in any of the plethora of cells you're not using, or in a Note or a Comment.