
The North Face
Wawona 6
Spacious vestibule, strong in storms, but rainfly tricky solo.

Running these analyses costs money. Buy through my links to help keep lights on! I may get a small commission.
If you have the budget Hilleberg. I have a Nammatj 3 GT. Indestructible and very comfy in bad weather.
I've had nice nights in Norway, Sweden and the northernmost part of Finland in Hilleberg tents (Soulo, Akto and Nammatji GT) and a Fjällräven tent (discontinued Skule R / S 2). It makes sense those tents were developed by people who hike in these very areas. I don't have any doubt thre are many tents that do the job well at half the price or less, but when a storm strikes, you'll feel safe in a quality tent.
The ones I have experience from are somewhat old models, I don't have experience on the ones made later on. My current tent is the Akto, and going together with a buddy of mine, we use his Nammatj GT. In general, I might recommend deciding on whether you want a tent that's also suitable for winter use or is 3-season use enough: the "red label" ones are winter tents, "yellow label" ones are three season ones. For the rest, I think it's a matter of opinion: some are ready to compromise in space and vestibule size to save weight, others consider space so valuable that the extra weight is justified.
I have the Nammatj 3T. It’s great
My 3 person Hilleberg Nammatj is still roomy with two people and gear. But then again I don't drag my entire living room out with me to go "camping" and am of the belief that you can enjoy the outdoors without dragging a circus tent out there.
What you've described is a Hilleberg. I don't think any other tent beats a Hilleberg in terms of strength to weight. I went with the Nammatj over the Nallo, mainly because I prefer the ventilation on the Nammatj and I prefer the door placement, but it is heavier than the Nallo. You won't be disappointed with the Nallo, or any Hilleberg for that matter, they are awesome.
Multiple tents is the only sensible option but honestly if it had to be one tent I think the Hilleberg Nammatj is up there. It has really big vents both front and back and full mesh convertible door. You could probably makeshift something to lift the outer fly off of the ground for the hottest months.
It'll probably hold up just fine in typical 3 season weather. But looking at the fading dye, it's seen a lot of use. Even with good care, it's a sign that the nylon may not be as strong as it once was, so I personally wouldn't trust it in harder winds. Especially when weather can be variable in the wild. Personally, if I was looking to get a nammatj, it's for its 4 season capacity, and knowing that i can trust it to stand up to unexpected changes in weather. Indeed, that's exactly what happened a few weeks ago. Set up with expected mild weather, ended up with 50mph gusts all night. Noisy, but felt safe throughout. This is especially in light of reasonably capable tents within that 600euro price range.

The North Face
Wawona 6
Spacious vestibule, strong in storms, but rainfly tricky solo.

Gazelle Tents
T4 Hub Tent Series
Fastest setup, durable, but bulky and awkward door.

Durston
X-Mid 2
Ultralight, spacious 2P, but not for very strong winds.

Durston
X-Mid 1
Budget ultralight 1P, spacious, but large footprint.

Naturehike
Mongar 2 Backpack Tent (Nylon)
Budget 2P, spacious for price, but not for 4 seasons.

Ranked #1
Durston - X-Mid 2

Ranked #1
Gazelle Tents - T4 Hub Tent Series

Ranked #1
Gazelle Tents - T4 Hub Tent Series

Ranked #1
Durston - X-Mid 2

Ranked #1
Durston - X-Mid 2

Ranked #1
SlingFin - Portal 2