So I keep coming back to this same idea in my head again and again: Renascent Infiltration and Chain Havocs. Really, there's all kinds of fun ideas for Renascent Infiltration, but this is the one I keep coming back to. The biggest issues with the Chainreaper are range and survivablity of the bearers. Which always meant a Rhino, which pretty much always meant forgoing shooting on turn 1 anyway. So it seems like a decent use, and if you can gently nestle those Havocs into some ruins in the 12"-24" range, they should be a right and proper burden to shift. Plus Conceal exists in case of emergency. Do keep in mind... at no point am I planning to take this to anything remotely competitive. This is just for normal matched play casual games with me and the mates, whom play DA and SW.
I keep running through other ideas, but nothing else is really jumping off of the page at me in the same way. Sure, there's the obvious use for melee bombs. Being able to deep strike Berzerkers (or Possessed)? Sure, why not! If going that route, double-down and throw Faceless Commander on an Exalted Champ to join them. But without the arsenal of charge-boosting tools other Legions got (save the Icon of Wrath, obviously), I don't know that it's the best use of the XXth's resources.
Chosen, I guess, isn't a terrible idea. A suicide plasma bomb is a way to go, with added jump pack Lord support can't hurt. 12 overcharged shots is a fairly solid volley. Then again, if that Lord is Clandestine with the Shadowblade, maybe it's not total suicide (thanks to Conceal). Or just combi/axe Chosen instead for a small harassment unit. Hm.
While not offense, the fact that Renascent Infiltration could also be used after falling back is a delightful little trick. I doubt it will often be necessary or helpful, but it could sure be a thorn in someone's side. That lone survivor of a combat slinks away, then pops up unexpectedly to grab a late game objective. Very niche, but it will be so satisfying if it can be pulled off.
I guess that's my real issue... I'm overflowing with ideas, and have yet to actually make a list.