This is an awesome reply. Most of what I wanted to say. I would add one more thing which is in agreement with everything else here.
My thread title for obvious reasons lead initial posters to believe I was targeting a nerf. My goal is to broaden viable strategies.
"Eldritch Blast is really the best damage dealing cantrip" only with Agonizing Blast invocation and Hex against a single low AC enemy at range.
In play the 120' range is almost always sufficient to give 100% up-time. It's true Agonizing Blast is essential: it's an example of narrowing viable strategies by making one strategy over-shadow. We've discussed a few ways that it can be improved. One is to make it a class feature rather than an invocation (if something is so good you have to take it, you might as well have it as an auto-pick... and one could argue that not doing that sets up a trap for new players). Another is to make it apply to other damage-dealing cantrips. I've tried that in some dummy runs, and experientially it did make me feel a lot more like casting things such as Frostbite, Ray of Frost, even Toll the Dead.
A single low AC enemy? Warlock's chance of hitting with EB is as good as any other character's, their range is often better, and they can divide the bolts for maximum efficiency. It's amazing in play how often the correct answer turns out to be "spam Blast".
The Pact of the Tome Warlock could take Sacred Flame or Lightning Lure and stand right next to an enemy (in 5ft), using concentration for Hold Person/Monster vs a Wisdom save and have a 100% hit AND CRIT rate.... which will make the damage of Eldritch Blast look bad not to mention the rest of the party jumping in on that.
It's a nice scenario. In play, these setups often don't work out as well as they sound on paper. It can happen, no doubt. The experience will be different depending on tier. Up to tier 3, the Warlock has two spell slots and could use Hold Person. The foe must be humanoid. They give up their first turn to cast it. (Sometimes the range will be an issue, but often not.) If it lands, they spend a couple of turns dropping that foe. Spells with saving throws can't critical, so the benefit is hitting a bit more often: prima-facie I think spamming EB will work out about the same for damage, and better by tier 3. FWIW it'd be better to cast Hold and hit the target with Blast, which can critical. In many cases it'be be better to Fireball with the slot, and then switch back to Blast.
Toll the Dead is far more effective and reliable vs high AC enemies in 5ft, attacking prone enemies (Hold him down Tank, I got your back), attacking enemies from prone (take that you stupid archers!!), enemies with cover (Ya hide from this!), or general close combat losing concentration is strong possibility or you need concentration for something else like "Protection from Good and evil", "Earth Bind" or Fighting in Flight using the "Fly" spell. In Fact, Wisdom saves are generally so much easier vs high AC dumb brutes that unless your fighting Clerics, Druids, or a scout of some type with higher wisdom its generally a more reliable option.
With RAW as it stands, Toll is okay in tier 1 and then falls terribly behind. Part is that it doesn't scale as ferociously. Part is the shorter range and conditional resulting in more circumstances where it lacks 100% up-time.
Chill touch for stopping enemy health regeneration that is faster than your damage.
Trolls and Vampires. Vampire Trolls! I wish Celestial had a feature that let them make Eldritch Blast deal radiant. I as saddened and surprised not so see that!
So... The OPs dislike of "Eldritch Blast + Agonizing Blast + Hex" is pretty much based on an incorrect over valuing of Hex
It's not, but no one likes a nerf. That said, I think, probably the only feature these boards agree on the evaluation of, is GWM! And I don't feel like GWM needs a nerf!! I really use the all-in melee attack as the standard by which others are judged. Ranged attacks for me should be about 2/3rds the damage, to be ensure non-ranged strategies are viable in play. Part of that is up-time. Part is safety.
which is good but not nearly as powerful as stated because when it's best is vs a single target with lots of HP to hit with as many Hex triggers as you can... your usually fighting a boss with High AC which then levels it back out. Occasionally you get a low 13AC giant but they also have a -1 wisdom save... An adult Black dragon has high 19AC and +1 Wisdom modifier so your more likely to hit with Toll the dead and burn those Legendary Resistances to open up more fun toys!!
I think Hex shouldn't be counted as 100% up-time. Sometimes the Hex falls on a target that turns out not to be the best one to attack, or goes down before the Warlock attacks it, or runs off, or whatever. I count Hex at 65% up-time in my balancing estimations.
An adult black dragon would be a tier 3 encounter. The chance of hitting with Tolls isn't too much better than with Blast, given
8+stat+prof+misc for saves vs
roll+stat+prof+misc for ranged spell attacks. Adult black dragon has +6 on the save, or 19 AC so the difference is 5%. Blast at tier 3 is doing 3d10+15 at 120'. Toll is doing 3d12 at 60'. Dragon flies (speed 80').