,restore balance--nihilith (Modern)

I've been on this archetype only since Ryan Cubit won that event in Australia early July 2016 with his postless list.

http://mtgtop8.com/event?e=13015&d=275944&f=MO

Shortly thereafter, this list placed:

http://mtgtop8.com/event?e=13107&d=276685&f=MO

I tried the blue version Cubit used, but I didn't like the mana, so I replaced Ardent Plea with Demonic Dread and Riftwing Cloudskate with Nihilith to stabilize the mana. Blood Moon is a bitch for our four-colorness, but search for tomorrow fixes that, and it replaces the subpar Baloth. Nihilith(it should be noted that Nihilith was part of the OP decklist on this thread) is an evasive beater that resolves from suspend way sooner than opponents expect given that so many of their cards hit the yard when we go off; plus the "may" ability makes sure we never lose a Nihilith to our own sweepers. It makes a fast enough clock that I have outraced a Tarmogoyf with just one Nihilith for the win against Jund. Speaking of Jund, this list is very strong against Jund and Infect; the jund players in my meta sincerely belief RB is one of their most difficult matchups. Unfortunately, we really struggle against super-fast aggro like Burn and Zoo, especially spell-based RDW-style decks. These sorts of matchups are where I lose the most, hence the Finks (the newest addition; I figure it can also provide a body or two to sac to Gargadon). The control matchup seems pretty even; Outburst EOT into Dread during your turn wrecks them, and Ricochet Trap and GDD from the board are just awesome. Six cards for burn in the board, plus Chewers for Chalice of the Void on 0 and/or Affinity, and Ravenous Trap for Dredge.

Going forward, there are still 8 slots that remain up for debate: 4x Search, the 2x Finks, and the 2x Beast Within, although a strong case would have to be made to remove Search as it fixes mana, enables turn 3 nahiri more often, and provides another land to sac to Gargs. Mardu Charm, Maelstrom Pulse and most recently Vendillion Clique was mentioned for these slots (although my list isn't blue ATM I am really down with the outside the box nature of that choice); what do you think would be optimal for those slots here?