One thing I'm waiting to see is how Giacchino is going to be able modulate this theme and deliver it in new contexts. That's one of the markers of a truly good theme for me.
Zimmer was doing this constantly with a lot of his themes, changing how the two-note "Bat-call" resolved in different scenarios, expanding on the themes with each film. Or stuff like how the original "Mollosus" theme from Begins originates with the notes the solo choir boy sings after the Waynes are murdered (and again when Bruce 'dies' in Rises). These are fantastic things you can do when you have a melody that you can play around with.
And I think Elfman's body of work as a whole on the character sometimes gets massively overlooked by fans too. Even if you want to say Walker's theme was superior (I can get on board with that) he brought a LOT to the character beyond just the main title version of the theme. Descent into Mystery, Finale re-contextualize the theme in epic fashion and are all-timer Batman tracks. Not to mention the entire Batman Returns score being a masterpiece.
I really do like a lot what I'm hearing so far, but my one concern is I think the theme does feel a bit repetitive. It's a great build-up, but it's something you can only do so many times in a film without feeling bludgeoned over the head IMO. I'm kind of surprised tbh that Giacchino didn't go ahead and write a lead melody for the theme or some kind of counter part, and instead opted for layering octaves on a simple "riff". Obviously reserving judgment until I see the final film, and there's always a chance he evolves it over time. But for the type of composer Giacchino is, I am a bit surprised to not get something that feels more fleshed out right out the gate.
Full disclosure, music production/composing is a big passion of mine, so I like to get a bit in the weeds on this stuff. I'm stealing this post from a composer forum because it perfectly sums up about how I feel so far about Giacchino's use of minimalism vs. what I think worked particularly well about Zimmer/JNH's:
HZ and JNH's uber-minimalist take works beautifully because it's doing a more wandering, searching thing, and actually has a point of resolution that you're aching for (especially in Begins) when they finally hit that bVI chord. The execution is brilliant -- musically, mix and production-wise, to picture...the whole thing just nails it. Giacchino's minimalist riff is more about a driving thing, angry and forward-marching, and so it appears the point is to hit you over the head until you like it. Perhaps that's the point, a la Zack de la Rocha screaming "f*** you I won't do what you tell me" for 2 minutes straight -- first it's awesome, then it's annoying, then it's really awesome. But so far I'm not really getting that. There's no sense of resolution or anticipation. Just repetition, hoping that you glean some profundity out of it in time.
I like it more than this person, but I also 100% know what he means. Zimmer's version makes you really ache for it to resolve on that VI chord and it feels so satisfying when it
finally kicks in with that huge swell. The new theme hits you with it repeatedly. There's also the fact that a lot of average listeners are saying it reminds them a bit too much of the Imperial March. Of course, both are based on Chopin's funeral march. But I think when both take that influence and blow it out into something so bombastic, the comparison is inevitable.