I'd choose a rector build because I foresee a weakening of shardless BUG and Jund, thus a general decrese of deathrite shamans: in this scenario rector is more likely to resolve it's ability.
I don't have a list atm, but I think I would play a copy of
runed halo as an answer to jace and true name nemesis, as well as a number of maelstrom pulse and vindicate as catch all answers (I think the correct total number is 3).
Obviously they need to be played along at least 3 pernicious deeds.
This should handle the fair matchups.
Against combo the red versions get slaughter games which is the nuts. White combo hate is represented almost by hate bears so I'd stick with more discard: I'd play at least 6 discards main deck. I would also like to play a couple of liliana of the veil right now, since she's good both against combo and blade/delver decks.
One card that I come to dislike is eternal witness: in theory is great but I found her very slow, sometimes too slow, and with all the DRS, oozes and rips around is not that great. I think I'd play one copy right now.
Although you want to play recurring nightmare I recomend to use it as a complementary strategy, ideal for grindy matchups: but remember that nic fit is all about discard-ramp-blow opponent's board and this should be your primary strategy.
For recurring shenigans I recomend thragtusk, kokusho and, if you have an instant sacrifice outlet like tower of phyrexia, faceless butcher: with the proper timing it exiles the creature, no question asked. Also, he's good against sneak&show because it's out of pyroclasm range.
Good rector targets are, apart the one already mentioned, primeval bounty, aura shards, oblivion ring, phyrexian arena, moat, chains of mephistopheles, choke...
This post it's like a collection of thoughts, sorry for that ^_^