Just to maybe address "the size thing".
We don't know the weight of this lens, and though the length is there, we don't know fully if that's dead on. But the square metrics for a high performing wide angle that this lens optically competes with are:
- Zeiss Otus 28mm f/1.4 - 1390g, 109x137mm
- Sigma Art 35mm f/1.4 - 665g, 77x94 mm
Neither of those are native RF lenses and likely could be made differently if designed now for mirrorless mounts. But in terms of quality of optics that's sort of what we are expecting to compete with.
For references of the older EF design:
- Canon 35mm f/1.4L - 760g, 80.4x105.5mm
Key thing being the older 35mm f/1.4L is an older design and not in the same class as the newer and modern aspherical design, likely coatings, glass itself, and finishing methods. Not a bad lens by any means, but Canon has already put the stake in the ground on where L-Series optics should land and it should be "ideally" above the Zeiss and Sigma primes at this point.
Sony's GMaster 35mm f/1.4 - 524g, 76x96 mm. This lens is lighter and made for a native mirrorless mount, but also not necessarily "better optically" than Zeiss and Sigma in this case. Nikon doesn't have a f/1.4 or faster Z-mount lens yet, but their older G is 600g and in the realm of performance of OG EF 35mm f/1.4L.
If we're talking 154.96mm long and making a an educated guess the new 35mm will land in the 885-1200g range. But the RF shorter flange could save maybe 200 grams potentially, but I'm hoping certain sacrifices on image circle won't be made. Unless theirs a bold new optical design that incorporates molded plastic elements, which I don't think they will do with this particular lens. Also potential of shaving off weight with a very complicated aspherical design, but hoping they don't go too nuts on that front as it will hit price and likely rarity if it's too hard to physically make well and consistently.
Outside of all the specs speculation and mulling over if this or that, the lens itself must produce a pleasing image and in this case also be high resolving and what we would consider the best that Canon can currently produce, hopefully highly corrected optics. All of this for many of us is priority number one and the rest of those chips pertaining to weight and size fall where they fall for a lens like this within reason.
I should underline, if you have the former 35mm f/1.4L EF and test it against the newer 35mm f/1.8 Macro RF, this likely alludes to some of the reasons Canon might have taken their time to find where and how they can improve any design with a faster/wider aperture. And I think this will contribute to good things for those wanted wider fast primes as well.