It depends on what are you testing by launching MVP. MVP is use to run an experiment to test (validate / invalidate) business assumptions (Customer, problem, solution , channel ... assumptions). If your are interested, I can share some material about MVP and validating business assumptions
It's good that your app has some traction. I have a classifieds ad site too (targeting Canadian market). Initially I was wondering if I should use WordPress or created it using MVC I picked the MVC approach. The thing is when doing the MVC you have to implement most of the functionality yourself ...