Regardless of the mix of types of data in one table, the data type in the individual column should drive the alignment.
Typical alignments (and of course, there are always reasons and ways to do differently)
- Text and items treated like text: Left Align (caveat: I find numbers
always easiest to read rt aligned)
- Numbers and items treated like numbers: Right Align (and if you have
decimals, best to always show, even if the one number is 23.00 and
another is 1.23)
A quick look at a grid with mixed data on the Bloomberg site shows a good example.
This grid shows a mixture of values, notice text is left aligned, numbers are right aligned. This makes it easier on the eyes and the brain for digesting the information.