Help me choose a blanket for co-sleeping please?

[MrsKitty]

DC2 is on the way, due October, and we have bought a bedside cot with the intention of semi co-sleeping IYSWIM.

Am paranoid about the whole duvet issue so plan to ditch it entirely till baby is bigger. It's going to be cold though for a good few months from October though I imagine so I am looking at alternative bedding. I know sheet/blanket is the recommended alternative, but what type of blanket?

Acrylic cellular blanket (cheapest option)
Wool cellular blanket
cotton blanket
Merino Wool Blanket

I know I'm being a bit PFB about this, but hey - I'm looking to get as much sleep as possible for all of us this time around

I coslept when DS2 was a tiny baby (moved into his own cot around 4 months).

I used to wrap the duvet around me so that I was lying on it, there was no way it could escape from my gargantuan weight .

I put him in a sleeping bag once he was heavy enough.

fruitstick I did the same on on the occasions when DS1 would come in with me, but could never get comfy or relaxed...Never knew blankets could be quite so expensive though