The scripting in Calc seems archaic compared to what comes with Excel.
Scripting? You mean like the VBScript crap? That may be true, but, IMO, if you're really using that, you're using the wrong tool anyway. If not, I'm pretty sure that Calc supports all of the functions that Excel supports natively. The only real incompatibility I've seen is that Excel will accept either commas or semicolons as delimiters for function arguments, and Calc only supports semicolons. Or something like that.
The integration between other apps in the Office family feels lightyears beyond OO.
What kind of integration are you wanting? Because I don't think I want any.