Orruk Warclans Army expansion and Alliegeances tips needed

[NeoSoul]

I am still new to AOS.  I won my first 5 games against many different armies with the Start Collecting box (470 points).  I then tried my Megaboss on foot but still had to go with 500 pts so I traded the Warchanter out and lost.  Then I finally got my brutes so 750 points but lost to Legions of Nagash.  I now got my Morgok's Krushas cause I loved the models so that could push me to 840 points.

What would be the best things for me to grab next?  I really love the Brutes models so I'd prefer to go with more brutes than Ardboyz if possible.  Here are some of the things I'm looking at for next purchases:

 

1- An other Brutes box (some with extra range so I could have a unit of 10)

2- Maw-Krusha or Gordrak (Gordrak seems more interesting but I prefer the look of the Megaboss on Maw-Krusha and people say it's better... still not sure I understand why he would be better though even though I know it can be customized, Gordrak's buff and dmg output seems possibly better while the +1 save defensive bonus seems good for the Megaboss but it seems hard to skip the free Mighty Destroyer each turn).

3- A 2nd Start Collecting box (I could definitely use 3 more goregruntas with polearms and a 2nd warchanter as my army grows in size... not very excited about having to build and paint a 2nd set of 10 ardboyz though but I know they can be quite good).

4- A weirdnob shaman (people say he's very bad but the unreliable teleport spell might be interesting and potential extra CP per turn and ability to try to unbound enemy spells?) OR a Fungoid Cave-Shaman (I really don't know much about this one)?

 

Then still looking at:

5- 3 more gore-gruntas (not worth it I think because of the price tag compared to a 2nd Start Collecting box).

6- Rockgut Troggoths (they look cool and decent unit that would also give me a ranged attack but not ideal since I can't buff them I think).

7- Dankhold Troggoth or Arachnarok Spider (same as above).

8- Ironjawz Ironskull's Boyz (very cheap but also apparently not very good and models look soso).

9- Bonesplitters (would be forced into Big Waagh! and I'm not sure I really like the models).

 

 

I am also wondering about Big Waagh! vs Ironjawz Alliegeance.  I think BW seems possibly stronger but that I need a full scale army for it to work (can't do it yet).  The Ironjawz warclan bonuses (Ironsunz and such) don't seem very good and I lose very powerful customizable abilities on my Megaboss for it... if I were to have Gordrak, can I pick one of those and he will be unaffected by the traits (how does it work)?

 

What are your thoughts on Gordrak vs Megaboss on Maw-Krusha?

 

Finally, I don't really know how I'm supposed to deal with Legions of Nagash.  I wiped out like 30 skeleton units several times but they were brought back to life each following turn and I ended up getting stuck in that army, unable to go snipe his heroes at the back of his army (I did kill one but a 2nd one was still far behind).  How do you approach those kind of armies as Ironjawz?