Aggregate several attributes into one using PCA
I see. Yes PCA is a good tool that you can use on your choice of attributes. The tricky part is that PCA is based on variance. Hence, if you have 2 attributes which are more important and have low variance and then 5 more with a lot of variances then the latter will be predominant on the first PC (I guess some standardisation would help). Hence, maybe it makes more sense to incorporate some corresponding weights on each attribute, a weighted average for instance (dummy example, but may fit the cause).