It took me a while to get the feel for pacing, and I’m still not that great at it. I find practicing during farming helps a bit.
So you might just need to give yourself more time to practice.
I posted a few videos last time, which are maybe somewhat useful: 📘 New Fables of Grimforest Challenge Event – FAQ, Discussion & Summoning Results - #300 by zephyr1
I don’t think Emblems or Troops are at all necessary. They certainly don’t hurt, but they aren’t needed.
This is the first Challenge Event that I’ve had any Emblems on 3* at all, and it was only +3 on Hawkmoon and Rudolph. I put them on for Raid Tournaments more than Challenge Events, and it’s only one single attack node on Rudolph between the two of them, so it certainly isn’t impacting damage output by much.