So, requirements:
Learned since we last met her: Pretty easy since I think we've only met her once before early on?
Fruity: Easy enough
Under 300: Sorta silly, pretty much all our drinks are under that. I can't tell if she's asking for an expensive drink here or a cheap one and just has a poor grasp on prices.
Secret requirement: She dislikes sour
Other info: We know she likes the 90500 Special, consisting of 2 parts wet jet to 1 part Sucrosol with a dash of Martian, it has a very sweet and fiery taste with a hint of earthiness.
Choices to look at imo:
Sugar Arsenic is extremely sweet, fruity and firey, a taste profile we know she likes, although the balance is off. 75c
Deep Red Flower has a complicated flavor profile, heavy on fruitiness but tastes of sweetness, bitterness, earthy, and soft. A complicated taste for a complicated customer, it's more complicated then what she's had before so we don't know if she'll like all of it, but it's not sour and its main taste is fruity 157c
Blue Fire goes down hard with the firey taste of Woda offset by a shot of fruity and sweet Buenberry. Balance is very much away from fruity here, but she might appreciate it all the same. It's cheap to boot. 51c
Sugar rush Fruity and sweet Grenadiere "offset" by even sweeter Dee tee. A simple but solid choice. 105c
Simpleton Our most simple drink, if you want fruity, that's all this is. 52c
Capricorn A very fruity soft and quite sweet drink. Strikes a line between the complications of the Red Flower and the simple nature of the Simpleton or sugar rush. 151c
Capricorn is a straightforward choice, Deep Red Flower if we want to show off.
In the end, I'm voting
A: Capricorn