Well the only exchanged that got hacked and returned stronger that i know is poloniex,i didnt know they had been hacked in the past.Soo for this small exchanges maybe its time to reforce the security.
I am not a fan of altcoin exchanges, but poloniex is the only exchange that did the right thing after they got hacked. And it shows as it came back stronger than ever as you also mentioned. Usually when an exchange gets hacked, many people will leave that exchange. But not in this case. The honesty and the correct approach of poloniex is received very well by its custommers.