The weight hierarchy
Lightening a shelter saves more real fatigue than lightening a stove or a headlamp, because a shelter is both weight and bulk. A pack that fits properly beats a pack that is lighter but rides badly — shoulder and hip pain ends trips far earlier than two extra pounds do.
Where not to save
Sleep insulation and rain protection. Cutting a few ounces on a quilt rating you cannot trust or a shell that wets out is how trips become miserable. Spend there.
Picks
$$$
Two-person trekking shelter
Highest fatigue-per-ounce saving available. Also the hardest thing to buy well from a spec sheet alone.
Awaiting ASIN$$
Insulated sleeping pad
R-value is the number that decides whether you sleep or shiver. Cheaper than the quilt and just as consequential.
Awaiting ASIN