I do get where you're coming from. I've done one play-through of War of the Chosen and even, I wasn't setting out for records (18 months game time to victory). Didn't even touch the Avatar side until the Chosen themselves were dead, and didn't advance across the map until the currently revealed one was killed. This made the Assassin the only actually tricky one as I had nearly full 'end-game' gear and max leveled squads for the next, certainly by the third.

My biggest irritation on the Alien Hunters/Shen's Last Gift integration was that there was effectively no in-game explanation. I had done Shen's prior to WotC so I was mostly expecting that, instead, zilch. Just make sparks from the start. So when I did encounter the rulers, Central telling me they were made by Vahlen came from left field entirely. No lead up, no advanced briefing just 'There! It's one of Vahlen's escaped experiments!" I spent a moment just blinking in confusion. Then attacking and getting annoyed with their mechanics.