The h index

I was explaining to a.colleague how to calculate.the h index of our department, since he got surprized that an emmeritus professor of our department (who does not publish too much) appears three times in the list of the 34 most quoted papers. I explained that this is a problem of the h index (if II remember well, Hirch pointed to this in his paper): it gives too much value to old published papers, which, due to their long lives, received lots of citations. Then I got the idea of using a time-dependent h index, let us say, based on the list of papers published in a given time span (for example, the last three years). This will give a best estimate of the citation strength os a set of researchers. Of course, this time-dependent h index may be artificially inflated by the own researcher citing his own papers, thefore I suggest introducing a secondary index, which I call the citation strengrh, which is the number of citations (full) divided by the citations excluding self-citations. In my opinipn this index computes the probability that an article published by that author is cited by someone else. I would like to hear your opinion about this idea.