Field test solo mission under the stars – FAIL!

Camped out last night to field test my kit for a bigger trip. Slept maybe 1/2 hours of brutally light cold sleep. I did sleep under the stars, as there was no wind but I thought it would be interesting to push the limits of my set up to see what it’s capable of.

NeoAir NXT R value 4.5
Cumulus Vencer 100 3/4 bag
Mont Bell ex light anorak down jacket
Mont bell fleece
Mont bell rain trekker
Merino wool T
Merino wool Universal Colours socks / Merino wool snowboarding socks (feet were warm all night)
Knee warmers
Soft cotton PJs
Beanie
Gloves

It was a total whim and I thought this would be more than enough. I was fkn Baltic!!

Shall I use it as a liner, or put it in an insulated bivy?

Or just get a new bag?

And how much would a tent actually make a diff? (I have Lanshan 1)