Hello, Ive been where you are, its very soul destroying but not hard to fix : )
Good start with the straight leg jeans, they make a huge difference imo. Shoes wise, ballet pumps in a good neutral colour for day to day, then into flat boots come colder weather I find works well
Find tops that arent clingy, either woven fabric or even silky type, I like printed tops as the print seems to distract the eye from my less than perfect shape. I then choose one of colours from the print and get a cropped cardi to wear on top.
While its still mild weather wise I get a lot of wear out of jersey blazers, like these , to me they smarten up my jeans and ballet pumps uniform
To be honest I find getting a really nice jacket the key to looking "pulled together", there are loads of nice barbour style jackets around for winter, if you have on one of those with nice dark jeans and knee high boots you will look great.
One final thing, the power of a great leather handbag and a nice printed scarf should NEVER be underestimated. What about choosing a bag in a bright colour you love then finding a print scarf that coordinates.
Yeah so:
Stick with straight dark indigo jeans
Ballet pumps for now
Knee High boots for colder weather
Non Clingy tops and coordinating cardis
Nice blazer for now/warm jacket for winter
Fabby Bag and co-ordinating scarf
Make sure everything you buy co-ordinates, then you'll never be stuck for an outfit