You're not forced to do Sekhemas, but the Chaos trials are higher level so you have to ascend later if you do these instead.
As long as you're ranged with strong damage, Sekhemas isn't that bad if you get some honor resist relics ready before you run. And yeah ES helps a lot too.
Ultimately the biggest issue they BOTH have is they're way too fucking long. It shouldn't take near that long to ascend imo, they need to cut down the amount of shit there is in there, regardless of any other adjustment and hopefully the 3rd trial is also shorter. Sekhemas floors should be like half of what they are in trial 3 and 4, and Chaos needs to speed up the bullshit and cut some rooms too, and probably cut the keys while they're at it(make it like 3/6/9/12 rooms). In PoE1 even when you have dogshit layouts it takes like half the time to run on a normal build and with good layouts it's even faster, it's so tedious even when well prepared it takes so much time.