It sounds like you need just a more polished and groomed version of what you already wear - there is no point suggesting ballgowns and tiaras if your life isn't structured around loads of dressy-uppy occasions. I too work from home and really feel the cold and don't have loads of occasions where I need to dress up. My wardrobe largely contains the following - maybe you can get some ideas of how to mix and match items to get some outfits you're happy with:
Bottoms: skinny jeans (loads, in various shades of denim, black, white, khaki, some with ankle zips, some coated); couple of pairs boyfriend jeans; pleather leggings; harem pants for wearing at home; a few tube skirts (I wear with thick tights and ankle boots in the winter); good quality jeggings
Footwear (too many but a selection of mine are): Converse in various shades, nice white trainers, burgundy New Balance trainers; Ash hi-tops; ankle boots in black, brown, grey; knee boots; calf-length boots
Tops: blouses in black, navy, cream and various prints (Dorothy Perkins, Primark and Mango have loads of these and they won't break the bank); thin round-neck jumpers, long cardigans (can be worn with a belt). I do buy hoodies, T-shirts and sweatshirts but I make sure I only buy nice (not necessarily expensive) versions (eg a wool hoodie, not fleece, a silky T-shirt) and don't wear them with a really casual bottom half so that I don't feel like too much of a slob.
Dresses: tunic style, mostly, plus a couple of nice shirt dresses
Accessories: scarves are your friend (the right scarf can really pull an outfit together); nice leather gloves in winter
Outerwear: blazer in spring/autumn, knee length coat (ditto), parka in winter (a parka looks great over a dress and need not make you look like a slob at all).
Overall: make sure everything fits really well, is well looked after (washed and ironed properly) and don't keep wearing things that have obviously seen better days. I don't think you need to spend loads to look good but you do need to shop wisely, take care of your clothes properly and never ever say "It'll do".
Maybe look at Susie So So's blog - that woman is a marvel at taking simple clothes (jeans, shirts etc) and making them look totally fantastic.