My current my favorite coins to hold are
Crown (CRW) - with plans to use masternodes to a fuller extent
http://crown.tech/about-crownCrave - low coin circulation and only 500 needed for a masternode. Don't let the freaky skull put you off this coin
https://www.craveproject.comPIVX - Custom zerocoin protocol implementation is very close, PIVX is a high quality Proof of Stake privacy focused coin with masternodes and a self funding + voting model.
+ and a few of the other smaller coins off
masternodes.pro I think masternode coins will take off so I'm planning on holding these for a while. Yes I know there's a lot of these types of coins but it seems like a good idea to create more crypto currency without the high gear or energy costs while holding a coin that's got other qualities aside from this.