I think it is harder at the moment op, as weather is crap and there is absolutely nowhere to go! With dc1, I was out all the time. A) this meant I felt the need to dress up a bit and B) she was well occupied with soft play, playgroup etc.
Now, we find we have to provide more entertainment at home. When I do go out, people don't see anything other than my coat and boots! I could be wearing anything underneath, even pjs, (I don't btw, but I could be for all anyone else knows)!
I do make an effort, but I don't wear anything which could get ruined. Anyone with two preschool age children, (been there very recently), who never gets their clothes destroyed is superhuman to me! Some people are naturally tidy though and maybe their dcs are too. I don't wear cashmere as I would have to wash it too often, but I compromise and wear lambswool or merino, which I find to me more forgiving, but still warm and looks good quality, for example.
I actually think having a good quality uniform is a good thing when you have more than one under school age! Even one under school age can be time consuming enough, as I have now, (homeschooling the older one atm obviously). I find having a naice mum uniform helps me feel put together with minimal effort!