Thanks for the open discussion of my PoSP suggestion guys!
I agree that changing to a PoSP system where coins in closed wallets don't earn stake interest would upset people who don't stake often ... but would that be a problem? You could always have a long lead time to give people plenty of warning to sell out of BTCD if they wanted to. CBX has been around since 2013 and they only converted to PoSP in Jan 2016.
I've never had the hardware for PoW mining, and I am convinced that the wasted electricity of PoW is a BIG adoption problem for btc, but I've always believed that the incentives for unknown parties to work together to secure the decentralised system built into PoW by satoshi are pure genius - the blockchain tech combined with the decentralised incentives of miners is the genius invention.
Unfortunately, you can't say the same about conventional staking. The incentives don't encourage people to support the network by staking because coins in offline wallets earn the same stake as coins in online wallets. There's a very slight compounding advantage gained by 24/7 wallets, but it's negligible.
In a competitive world the rational multi-coin owner like myself will stake for the minimum time required to earn their stake, then they'll close that wallet and open the next one. That's what I do anyway. I love BTCD for all it offers, but I don't stake 24/7, I can't.
I've been interested in PoS since Peercoin, and I've probably downloaded and staked nearly every PoS coin around, but I've never had the resources to stake coins 24/7, so I rotate the wallets I'm syncing at any point in time, but I never run wallets 24/7 ... until I discovered CBX and PoSP that is. PoSP incentives make me want to run CBX 24/7, so I increase my overall stake in the coin - I earn 8-14%, but inflation is only 2%. No other PoS coin I know of has this incentive.
Conventional staking where coins age in closed offline wallets is a zero sum game. You stake to tread water. It's like a standard bank account earning X% interest when the CPI inflation is X% also - the real return is ZERO! It's like methodone, there's no 'hit' as such, you just stake to not fall behind.
After 3 years of staking coins I'm convinced PoSP is the best algorithm to secure a PoS coin like BTCD. With PoSP you don't stake for a real return of ZERO, the real return is actually positive, and the overall effect is a lot more staking wallets, and a much more secure network.
I think it's a no-brainer!
edit: Here's the CBX PoSP whitepaper
http://cryptobullion.io/white-paper/