Deathrattle Escalation

[Skorp]

Hi All,

I'm playing in an escalation league at my local store as a way to build up my deathrattle army. We started at 750 points, tomorrow I'll be playing the game for 1250 points, each week will be +250 points until we hit 2000. We can change our list as much as we want each week.

I won the first game, and we made a rules mistake on the second game so we called it a draw but I feel like I would have had him otherwise. 40 skeletons pack a punch if they get in without taking losses. He is my most likely opponent moving forward and he is playing Tzeetch Arcanites. His lists have thus far consisted of tzaangors, kairic acolytes, tzaangor shaman, skyfires, tzaangors on discs. 

Right now my army base consists of the following:

Vampire Lord (Wings)
Necromancer
Necromancer
Wight King (On Foot)

2 Bat Swarms
10 Skeletons with Blades
40 Skeletons with Spears

I planned to add 10 grave guard and 5 black knights to the list for 1250 points.

10 Grave Guard
5 Black Knights
Aethervoid Pendulum (or leave it out for a command point to start)

Total: 1240/1250.

I'm working toward the deathmarch battalion when we hit 1500 points next week. Have 5 more black knights to build and have some lord of the rings army of the dead I could use for either more skeletons or grave guard depending on where I want the list to go. I've also got a magnetized mortarch, 2 morghast, 6 spirit hosts, unbuilt mortis engine kit, 5 dire wolves, unbuilt soul wars, 8 myrmourn banshees, and lady olynder. Also have a ringwraith on felbeast I was going to use as a vampire on zombie dragon if desired. 

My feeling is that if I'm going deathmarch I should bulk up the black knights and grave guard units. I feel like my heroes are a bit squishy and I'm unsure if I should add something bigger and when. 

Been debating also between grand host of nagash or legion of sacrament. Lord of Nagasshazar seems amazing with ossific diadem, but sacrament could be fun with more movement stacking with deathmarch. Based on what I've got going so far what would more experienced death players recommend? 

Thanks for reading!