UL Freestanding. Cheapest/lightest/quality

Not sure if you can get it down to 650g. That’s 22oz. You can get it down to around 32oz.

With only 3 contact points, the Nemo Hornet (or Hornet Elite) is really a semi- freestanding tent. Just like the BA Fly Creek UL1, it’s lousy in strong winds.

The MSR Carbon Reflex is similar weight with 3 contact points.

Even though it’s more expensive, the lightest and best truly freestanding tent is the Big Sky Soul in Cuben (Cubic Tech). Much more stable with 4 contact points and weighs 22.3 oz. Costs around $680, but the Hornet Elite is $450 and nowhere in the same league as the Big Sky Soul.

The Nordisk Lofoten is probably the lightest double wall tent in the world that’s not trekking pole supported. It features a large and small loop that breaks down very small, so I guess it’s technically a semi-freestanding tent. Weighs a tad under 18 oz and is made with a super high-grade 7 denier. You can see it on the ultralightoutdoorgear/co/uk website. Cost a little over $600.

I agree with your priorities.   I’ve been through a bunch of single person tents and my next one will be the Soul.    That front-entry is out of fashion but I find it easier to position in off-the-radar camp sites.    A symmetrical design is the easiest to place.   Side entry often causes an additional restriction in your site choice.    The Soul even looks as though you could get by without staking the fly in a pinch, which is still required for most so-called free standing designs.

I’m not a cuben fan and I’m willing to carry more weight than most around here.   I’d stick with the “value version”.