Suitable clothes for the cold?

Having decided to get used to the 18C minimum as an average for the heating I have decided to look again at the clothing situation! Found a whole pile of revolting sports socks I brought some years ago - ah well, at least they are warm.
When we planned for retirement we knew we would be downsizing and have less storage space.  Also I would no longer need the office clothes (hurrah). If you ever read Lee Child's Jack Reacher books you will know his theory of not having luggage - if he has clothes/stuff, he needs a bag, the bag and stuff need cupboards to be put in and washing machines etc, then he has the expenses of a house, etc..
For 2 years I deliberately wore out all the clothes of management and office work.  I no longer cared if at a conference I was wearing the same suit as last time.  At annual training things at least I had the last laugh of being able to say "won't be seeing you next time"!
I have worn a formal black skirt twice in the last 3 months!
I am not saying no clothes at all just not so many and planned for those I want for our new life of lots of gardening, walking, sailing and relaxing. Just having sufficient to wash and wear - with a few best outfits (it must be my 1950/60s up bringing - it was all we had then!)
But for the cold weather I am looking at layers of old t shirts and jumpers indoors with fleeces and thermals for wandering in and out to the veg plot.. I have found the GO Warehouse range is proving most useful at present. Next winter the few I have may need supplementing but I will have a better idea of what is useful and practical.
 I have treated myself to one thing this year  - a fleece lined shirt from Tesco's. OK it was in the men's range (nothing similar in the women's section anyway) and is a bit like a builders choice,  but it is frankly wonderfully warm and it will be perfect in our poly-tunnel planting out early crops once we have finished building it.
Over the winter/spring I will be looking to sew some loose cotton tops for next summer - having destroyed the last of the office long sleeve shirts painting fences this autumn.  I am sure making my own will be most cost effective - unless I swallow principals and shop in certain cheap discount shops who have unethical manufacturing ! I will try to avoid that.  Charity shops are an alternative but  cotton is rare find and anything else is not good for outdoor lifestyle.