Tent shopping is mostly about matching the shape and season rating to how and where you'll actually camp — the marketing photos rarely show the tradeoffs that matter once you're setting it up in real weather.
Dome vs. tunnel
Dome tents use crossing poles to form a self-supporting arch shape. They're freestanding (can be picked up and moved without unstaking), generally quick to pitch, and shed wind well from most directions, but tend to offer less usable interior space and headroom for their footprint.
Tunnel tents use a series of parallel arched poles to form a longer, more rectangular shape, offering more usable floor space and headroom for the same weight of materials. The tradeoff: they aren't freestanding — they rely on being staked out at both ends to hold their shape — and they perform best when pitched with the tunnel's length facing into the prevailing wind rather than sideways to it.
What "season rating" actually promises
A 3-season tent is built for spring through fall in moderate conditions — good ventilation, lighter materials, but not designed for sustained heavy snow load or extreme wind. A 4-season tent uses a sturdier pole structure and less mesh, trading some ventilation and weight for the ability to handle winter conditions and snow loading. Buying a 4-season tent for summer camping mostly just means carrying extra weight and dealing with worse airflow for no real benefit — match the rating to the conditions you'll actually camp in, not the most extreme case you can imagine.
The spec that matters more than floor space
Check the peak height and the shape of the usable space, not just the floor area in square feet. Two tents with identical floor space can feel very different to actually live in — steep, near-vertical walls (common in dome and cabin-style tents) give you more usable room to sit up and move around near the edges, while sharply sloped walls (common in some lightweight tunnel and backpacking designs) shrink the practically usable space well below the advertised floor area.
The one thing people forget
Set up a new tent at home at least once before the first camping trip. It's a much better time to discover a missing part or a confusing pole configuration than in a campsite parking lot at dusk.