Waves can't be the next ethereum. Yes they do try to make things easier for the end user, but they still lack customization that Ether offers. With Ether you can do whatever you want, while with Waves you are kinda restricted. The good things about waves is that its network is kinda more efficient, which means it can process more transaction and people don't have to wait long for their transaction to process. But experienced projects and developers usually go for Ethereum because they can program it according to their preferences and they are not set-back by already applied rules that Waves has. It doesn't mean that there is no market out there for Waves, it just means that it will be much smaller than what Ethereum has.
Even programming bugs that cause some millions to be lost "accidentally"

Waves is still under dev., but once they finish to implement the smart contracts, the platform will be better to use so far.
Waves is still very young, it's hard to compare yet.