You could leverage the People Performance Report for this. You could specify the conversion timeframe in the report's SL so you're getting activity data within the required timeframe (Q1-Q4). The people performance report allows you to add only one Group By field; so you can create separate reports with different Group By fields (Industry, Seniority, etc.) selected in each report. You could also add smart lists as custom columns, but you'd have to create a separate SL for each value of the field. You could also use Group By and custom columns together to see the data in two dimensions. There's a Drill Down feature in the people performance report using which you could drill down a specific row of the report further to see additional person info.
Also, this would be much easier and more precise if you accurately capture channel/source data from your marketing tactics on the person record (via UTMs, Cookies, etc.)
