Knowing this, I'm glad many of you answered the question by naming a specific uke. Some did answer the question that way and those who didn't still gave me something to think about; If I go to a builder for my next uke, I'll spend a little more time with
http://tonewooddatasource.weebly.com/, learning about some of these woods.
With that in mind, once you've narrowed this down further, a helpful (if perhaps obvious!) path forward would be to consider the overall results of your short-list tonewoods in specific builders' hands.
Meaning, I love my Rebel Concert in Acacia, but would not begin to recommend "Acacia" to someone else based on that alone. I honestly have no idea how much the wood itself has to do with the happy impression I have of this instrument, or how the same wood would sound in a different ukulele build.
Similarly, my Mango Rebel Soprano is a keeper ("sweet" seems such a generic, oft-applied descriptor when it comes to Mango's tones, but it really does fit), but again: I love this specific ukulele, built as it is, and don't have objectivity to recommend the same wood on other ukuleles (other than the Koaloha and Opio instruments which share the same lineage and outlook, so I'd venture would at least be similar).
My upcoming Beansprout will feature a Port Orford Cedar top (cypress family, actually) over walnut.
Why? I love Aaron Keim's now-many examples of the same -- visually and sonically- -- trust his recommendations, and am smitten by the looks of how he has historically arranged these wood grains within each piece and in juxtaposition.
An objective, well-researched source of information on various wood types, etc. can only help, but from there: look for those who have demonstrated the ability to make the most of the presenting qualities that appeal to you.
Have fun!
~ S.