With temps like 22f, I'd definitely think about doing a grill block.
Our temps are currently 35-40f mornings, 50f afternoons. A full lower grill block (left the upper open) has definitely sped up my warm up times and keeps the engine warmer when I use the heat in stop-and-go traffic.
It's a Civic hybrid, I just shoved two cut pieces of large-sized foam pipe insulation into the slots... I was going to zip tie it, but it's been so secure I haven't needed to