Hmmmm- I’d say it depends. Yes, absolutely, consideration and lack of boastfulness is good.
BUT, I think particularly women are often socialised to avoid taking credit where credit is due, or avoid expressing self confidence, in case they will be attacked for getting above themselves.
im not saying you are doing this, OP, but I do think it’s right that you assure her she has much to be proud of and that anybody who cares about her will be delighted for her. I hope she feels and knows that.
I know that I ended up in a first marriage, sub consciously underplaying all my achievements, because deep down I knew he didn’t want me to shine. I hope your daughter knows she is allowed to shine!
and her painting is amazing- the technique, yes, but also the character that shines through in the portrait. Fantastic!