I suppose that it would be too much to ask for Xrite to say what it should be.
Just use a good standard data set as reference for comparison.
I do remember, after buying an i1Pro, being sneered at by an Isis user and told that it was crap. If he was right, it was very expensive crap.
The i1Pro is a fine and versatile instrument. The Isis may be slightly more accurate for some things, but there's not a lot of difference in the end result, if any.
I have a number of Excel spreadsheets from my days with ColorBurst. I'll dust them off and take a look.
Just start from scratch again. Trying to re-use old spread sheets may be error prone unless you documented them well.
I haven't been near any of this stuff in a few years. It doesn't seem to have been made any simpler in that time.
I don't think there's been much improvement in the last ten years. Profiler might build slightly better profiles and have a flashier interface, but as Andrew has already said there's not much between it and PMP5, or anything else of that vintage.
Documentation is still dire.
The one thing that has improved is manufacturer's profiles now seem better and some third party materials suppliers seem to be making progress in providing quality profiles for their products too.