Multiclassing to save for feat selection? In 5E, my understanding is that feats require four levels in a single class, not four character levels... So if you want feats, you'd stick to a single class?
Knowing we'll get to play to level 10 in the full release of BG3, I can see how you dip two levels, but outside of that?
It is what it is, really and 2 levels dip in a class is worth it for benefits in very specific builds. For example Sorlock is popular which is Warlock 2/Sorc X or Warlock 3/Sorc X, where you literally get 90% of all the point in Warlock and actual full spellcasting ability, save a few slots missing, which does not terribly matter. That build can really pump some EBs there with Sorcery points, far better than Warlock alone ever could.
And in EB, the Warlock here is like half-implemented to begin with. Patron(s) missing and only 1 pact out of 3.
Some people do tend to lie to themselves a bit, reality is EA Warlock is probably the weakest class there is now. Like all these guys above making EB seem like it's such a hotshot spell, when in reality when you look at it - it's basically literally a pretty crossbow shot that knockbacks for free, but that you can't dip/coat in poison/have more attack with thanks to magic weapons. Quite frankly, the whole Hex benefit can be had by anyone as is, by simply using a poison bottle for weapon you get a ton of or dipping - that's free, even without doing that Hex feat trick.
And what you get to make yourself better than a crossbow? 2 Spell slots per short rest and a companion that can't hit anything to save its life that won't even scale further down the road.
So yes, Wyll feels weak, because that's simply how it is. Sometimes things are just as they appear, really.
I mean I have firsthand experience - my first PT was Warlock PC and I optimized all I could and like guys above when EB connected with hex and all I was like "woohoo, feels good"... My second playthrough - Ranger... it's like night and day, you literally do twice the damage with normal attacks with Ranger and at better hit chance and you can start out with 9 proficiencies to boot, so like... what's the point.
And that's even without all the EA cheese/bugs people do, like Wizards oneshotting dragons with thunderwave or rogues rolling in 50+ damage per turn without breaking a sweat or rangers/rogues double/triple proccing GWM for absurd damage.