I need a Calc which doesn't suck. I don't necessarily need Excel, but the spreadsheet shouldn't be unusably slow at 100x100 cells with simple calculations and a literal couple of V/XLOOKUPs.
I have gnumeric documents with hundreds of plots containing fits etc that I view in 4k without any lag or delays whatsoever. The plotting options can also be made suitable for publication much more easily. All the important functions are there.
My main complaint about spreadsheets in general is the fitting options are still in the stone age compared with software like ROOT using minuit, where you can easily do a proper chi squared minimization with arbitrary functions where error bars of all points are correctly used. However, it seems only the sciences use such features as apparently there is no demand from the business world (or other MS customers) for spreadsheet tools supporting thought or analysis beyond a 5th grade level.
Microsoft has had decades and millions of dollars to make excel usable, and should be embarrassed about how their flagship productivity software is rightfully seen as unfit for purpose by people doing rigorous work. Seeing nontrivial information in a scientific talk rendered in the telltale excel style is visual shorthand for "the real analysis hasn't been done yet" or "I don't know what I'm doing and won't be able to answer questions about uncertainties."