Nice video. I have too many armies at the moment and wanted to focus on my LRL this edition (haven't played a game yet) but OBR is my largest army, fully painted and the one I played more in 3rd edition. I have everything except for Nagash and the Soulreaper. Seeing this video makes me consider maybe finally getting Nagash (just wondering if his model might get updated at some point but I guess it'd still be far away) as the Morghasts are my favorite models. I was very bummed out when they revealed the new rules and the warscroll for the Stalker though because I used to play very elite armies with lots of Stalkers and Immortis Guards and the new Stalker warscroll is just so incredibly weak (they lost a ton of mobility, damage cut in half or more, less control, less survivability, no more healing/recursion, lost their subfaction and were given no new subfaction at all, etc.). These will most likely unfortunately stay shelved until a new book but it might be time to make use of those 20 deathriders again and Nagash being possibly viable looks interesting.
You can't cast Soul Guide on a Soulreaper (through magical intervention) to try to get a chain attack in the off turn. That's clear in 19.0. However, soul guide is still a strong defensive spell. Great analysis from the guest. I have enjoyed Stalkers as an anvil unit. -1 to hit, with a 5++ ward and being on Rend 3 because of counterstrike, along with naturally wounding on 3s absorbs, and deals out, more than you think. Mortek having a nonbo with counterstrike is incredibly frustrating.