I've had PS Plus for just under a year and I have to agree this is the worst month by quite some distance.
Don't have a PS4 yet so can't give an opinion on those games but having spent more time waiting on Luftrausers Vita downloading than actually playing it I won't bother with the PS3 version and I'm sure I've already played and disliked Frozen Synapse on my tablet.
The Binding of Isaac is clearly not my cup of tea, I got bored of that style of game 20 years ago. Can't be doing with a twin stick shooter that only lets you shoot at right angles, it's 2014 ffs.
The only game I've spent any time on is Escape Plan and I'm not even too bothered about that, looks nice but it doesn't play too great at times.
On the plus side (haha) though it has meant going through my old plus games to find something to play. I finally got round to Remember Me which was on Plus months ago and I wass very pleasantly surprised, very nice game with good production values,even though it's very unlikely I wouldn't mind a sequel.