POS and DPOS is essentially a framework where large stakeholders collect usury off the network and even if you have a very fair initial distribution model you will have unequal wealth accumulation over time because most of the profits are compounded instead of reinvested at a loss.
In Nxt, anyone can forge (possibly through leasing). It's not something reserved to the rich and powerful. The percentage returns are the same.
In Nxt, forging is something done to help secure the network. It's not done to make money. The income from forging is currently around 0.2%/year, which is trivial. It's expected to become lower once we reduce the fees. Validating transactions is so cheap in PoS, it leads to a different mentality to PoW, because there aren't millions of dollars involved every day. (That's part of why "nothing at stake" doesn't apply. The increased income you'd get from forging on multiple forks isn't worth the loss of security. NaS is a criticism only someone from the PoW world would make.)
With PoW you can easily know in realtime if there is a mounting risk from a mining pool, ASIC manufacturer, or miner.
Only if they choose to reveal their power, and only if they aren't suddenly hijacked by another party.
So you need a dedicated computer and internet connection to mine in a PoS schema?
No. For example, I have two Nxt accounts. One I use for forging; it has a zero balance so it doesn't need to be secure. The other stores the coins and leases to the forging account; it doesn't need to be public.
PS I try to restrict my comments to Nxt because that's the PoS I know best. Other PoS may have other solutions and/or problems.