This is such a wonderful concept! I've been looking for something that is similar to the original DS game series 'Style Savvy' forever! Fashion has always been an interest of mine, even when I was smaller.
Owning a boutique, in the 'Style Savvy' games, was special because it was more than 'buy clothing and look pretty,' it was resource management and trend prediction. This demo is so sweet and is very refreshing from the current market of cozy games. Dressmaker has so much potential to be something big!
I know this is just a taste of what could be, but I think it's important to voice some features I would love to see on final release. For example, a search section that lets you filter fabrics/designs based on style tag from the customer's request. Or maybe, a research tab that lets you learn new patterns for more dress-making options as you progress and hone your skills. 'Style Savvy' had small 'profiles' on the characters you meet, to help the player choose the appropriate product for the customer. This feature could give a bonus to the dress-maker's final pay for 'adding the customer's favorite color' to the dress when it was stated in the 'profile' or something along those lines.
Overall, a breath of fresh air to play and I look forward to any news about this game's progress.
((Also, I highly suggest the developers looking into the 'Style Savvy' game series for research purposes. There are a large amount of mechanics that I believe would work so well with this game.))