Sorry for a necro bump, but I can’t resist: as I continue learning more about the whole cryptocurrency world and know more about PoW vs. PoS (by experiencing the differences first-hand as an end user), I want to comment on how encouraging it is to see Zcash willing to change and innovate in such big ways when the improvement is clear and obvious.
PoS really makes things easier, faster, cheaper, and on the balance of things, safer, more reliable (on multiple fronts), and more ‘free’. Maybe there’s weaknesses I don’t know about, I haven’t read into the staking system very much - e.g. whether there’s concerns about easier centralisation by making the rich have all the power vs. the poor (which is a terrible situation from a cypherpunk perspective) - but what I do know is that Monero has been having major problems with one particular mining pool having 51% of the mining power, AKA it’s been prone to a devastating 51% attack on multiple occasions. So isn’t that interesting.
Not to make fun of them wantonly - decentralisation is hard. But perhaps staking makes it easier for people to join vs. mining in the end, and it’s actually more egalitarian, or, it pans out to have similar level of accessibility where people join in ‘staking pools’ vs. ‘mining pools’. (Kind of like DAOs to manage balances of power in the control of a coin.)
(Below is tangential / off-topic):
That Monero is so stuck in its ways shows that if Zcash keeps on innovating and improving, it might just become irresistible to a certain number of Monero users at some point. 
There’s almost nothing Zcash now has as a downside vs. Monero. (E.g. ‘trusted setup’ is now over - they can no longer complain about that.) Personally I think the dev tax thing has had extraordinary results. Economically participating in that doesn’t take any of my ‘freedoms’ away - and it’s no more centralised than agreeing to use software made by a small dev team in the absence of a dev tax. And as for decentralised governance? I haven’t looked into ZEC governance much nor compared it to XMR, but again it doesn’t feel like it’s taking away my freedoms to have extremely private transactions with other people on the Internet. It’s fully open-source, and communication is amazingly transparent. The obsession with decentralisation can veer into religion and theory - theology, not reality. Don’t get me wrong though, I do agree with it 100%.
So apart from more adoption needed of shielded payments among vendors of things on the Internet, there’s only one major privacy hole I’ve identified in the Unified Address design (though it’s relegatable by applying extra OPSEC practices), which is that people can still send you ‘shielding’ transactions to your Z-address or new U-address (exposing incoming transaction amount), even if you want ZEC to be default fully shielded in both directions, no matter what. I got very upset when I discovered that (and I want to apologise for that), but the fact remains that Zcash is far better than anything else, if the user has done their research - or now in Halo 2 and UA era, even if they haven’t. I just hope the ‘shielding’ hole is fixed one day. That’s what Monero community will latch onto to still claim that Zcash isn’t a legitimate privacy coin.
Forge on, heroes!