You name one good alternative for video calls... And by that I mean one that doesn't randomly delete chat history, doesn't have shit ping and one that can be used even with bad connection (hangouts lets you lower quality on the spot for less lag, which no other video calling option offers to my knowledge).
Also, the appeal of hangouts was that you could have it fully functional while on Gmail, so you wouldn't have to go back and forth and instead have everything in the same place. Plus, an ENORMOUS bonus thing is that integrated in it is Google Calls which lets you call actual phone numbers all over the world either for free or dirt cheap, so great for people who make a lot of international calls (also, you only need internet, so screw paying companies for call packages and shit).