This^ Also wanted to add that if ur looking for a budget win, I've found these work great for the a7C II: - Ulanzi TT09 VideoFast Carbon Fiber Travel Tripod - basically half the price of the Peak Design mentioned earlier but honestly super stable.
- SmallRig Lightweight Carbon Fiber Tripod AP-02 - only $100 and sooo light tho! I've used tons of gear over the years and these handle long exposures like a charm!

Hey, I totally feel u on this. I've got the a7C II as well and literally the whole point of that body is keeping things light. In my experience, you should definetly check out the Ulanzi lineup. Honestly, you can't go wrong with their carbon fiber options right now. I was skeptical at first cuz they're way cheaper than the "premium" brands, but for a setup like yours (especially with that 20-70mm G), it's more than enough. I mean, I've used some of their travel-specific stuff and it fits perfectly in my bag without weighing me down. Is it as rock-solid as a giant studio rig? No, but for long exposures, I just hang my camera bag on the hook at the bottom and it's basically solid. I'd just get any of the lightweight carbon fiber ones from Ulanzi or even Benro if you wanna save some cash. NGL, the Peak Design stuff is cool but I think you're paying a huge tax for the brand name. The vibration issue is mostly overblown unless you're shooting in high winds, lol. Just make sure whatever you get has a decent ball head that doesn't creep... that’s usually the real bottleneck with small gear anyway. It works for my street and landscape stuff without being a pain to carry. Good luck!

Exactly what I was thinking

I spent way too much time obsessing over vibration graphs when I first got my a7C II last year. Honestly, for long exposures, you have to look at torsional rigidity and not just the max load capacity. I found that center columns are basically just giant tuning forks for wind vibration, which is why I eventually moved away from the more mainstream travel designs. After testing a few, I settled on the Leofoto LS-224C Ranger Series Carbon Fiber Tripod. My logic was simple: it uses 10-layer carbon fiber and ditches the center column entirely, which keeps the apex much stiffer. The 22mm leg diameter on the top section is the sweet spot for a setup like yours. When I am shooting 30-second exposures with my 20-70mm G, I need zero movement. I also paired it with a Leofoto LH-25 Low Profile Ball Head because it keeps the center of gravity much closer to the legs. It fits in a standard backpack side pocket easily, and since there is no center column to wobble, it is way more reliable in a breeze than those flip-out travel designs.