Apologies for brevity due to phone typing.
-cumulative probability curves (at x months y % of customers came back OR 50% of your customers in this cohort spent more than X)
-relative time cohort analysis(how is you jan 2019 cohort performing after 1 quarter versus jan 18 and jan 17)
-cohort analysis in real time (a fixed event happened at date XYZ that impacted the entire business. What impact did it have on the each cohort)
purchase intervals by numer of visits (time)
Stuff like that