Bit melodramatic Freudian, op's daughter happens to like some clothes from Next, how does mean she is brand obsessed? They have to wear something you know, unless you want Op to take her to the park naked. How patronising. 
it's hardly princess crap, I don't suppose Op is taking her for spray tans and eyelash extensions.
Mine have had an opinion on what they want to wear since they were about two, both hate jeans, one likes pink and flowery and the other likes blue and green. They aren't obsessed with clothes, they care nothing about brands or fashion and of course they go to the park, play like anybody else. Why would having an opinion on what clothes you wear mean you don't do normal things?
I had opinions on my clothes too when I was little, but knew or cared nothing about brands, some of my favourite clothes were from a second hand shop. Once I wanted to go to playgroup wearing the same pair of maroon dungarees every day, I must have been about three.
Some of the smaller branches of Next aren't so busy, but the bigger ones are usually a bit manic. I've gone early in the morning, never at 5, though and been surprised how quiet it's been. Depends how busy the store is, as to whether you'd want to take a child with you.
OP, have you thought about shopping online? Although you do need to agree to take the Next directory, which they charge you for and a lot of stuff will have already gone in the VIP sale. If you sign up to their email you might get a VIP invite for future sales.