It seems to have increased the sales for less than 10% in my case, but since I did this only a few days ago, I cannot say with confidence that it had anything to do with the switch.
But it did reduce confusion about the product itself and therefore support emails. (just the fact that there were 2 ways to get the full featured app was confusing to many - but this pro only exists because my own stupidity)
Long term I hope (it may never happen) that less people upload and therefore download pirated apks, because those versions are often very outdated, and some downloads out there are even broken because of that, causing additional support requests and bad reviews. (I rely heavily on Facebooks APIs, which change quite frequently)
If someone asked me if it was a good idea to pull an app that has been out there for a year or longer (with 100.000+ downloads) and resubmit it again I would definitely say no, because that also means that you basically start from zero again - from 1000+ downloads per day down to 10.
I don't know how the rankings in the Google Play store are created, but it seems to me that being around for a long time favors your ranking and downloads heavily.