Few other suggestions that may help. You mentioned Grave Pact and Dictate of Erebos, but if you're going that way, I'd suggest going full on and also including Butcher of Malakir and Martyr's Bond.

Also there are some fun cards not from the Tarkir block that modify creatures with +1/+1 counters. Oona's Blackguard is a pretty handy one I use in my Daghatar deck. I'd also recommend Shinewend for removal, and Necropolis Regent, Renegade Krasis, and Mephidross Vampire to really help you get more of the counters.

wereotter - thanks for the suggestions. The butcher was already in my maybe board, and didn't even know about Martyr's Bond (will look for 2 of these - the other for my mono white edh deck).

Hey man, +1 on a solid looking deck.

A couple of quick suggestions: Merciless Executioner and Fleshbag Marauder are pretty good alone, but are REALLY good with Grave Pact effects. Also, Auramancer and Monk Idealist aren't bad if you want to go a little enchantment heavy, which by-the-by is completely doable considering things like Mesa Enchantress and Eidolon of Blossoms are cheap (and such good draw).

Sorry, tangent... Um, Daghatar the Adamant is kind of a bad Ghave, but a second Ghave is good, right? Commander's Sphere and such are also suggested.

I like it. Looks like the Daghatar deck I considered at one point but abandoned because Daghatar isn't a very good commander. Poor Daghatar.

It is a different route than the one I'm working on which is built for combo rather than combat, but I love the "counters matter" synergy and it seems fun to play. I'll have a look at that old list and see if any ideas pop out at me.

+1 just for the pun.