I was just thinking how nice it would be to have an IfError function like there is in Excel. With Alteryx's design, there isn't really much need for the function. I just ran into a case today where I thought it might be useful. There was a function created after a crosstab that expected certain field names to exist. I got around this by using filter, summarize, and join tools instead.
It just stuck with me that it would be much easier to just say:
IfError([FieldThatDoesNotExist],0)
Something like this could also be used when referencing a field which has a calculation that produces an error.
I don't know if something like this would be completely antithetical to Alteryx's design, but there are times when it would definitely be convenient.