I have been through at least ten iterations of this recipe. This was kind of a breakthrough recipe, so we'll just call everything before this v0.x

v1.0
cactus 1.5
key lime .33
lychee 1
orange cream 4
pink guava 1
watermelon 3

notes:

really good. Halving pink guava cured the harshness problem, and orange cream is a great replacement for the custard and tangerine components. It could be a little brighter, so I'm increasing the pink guava and key lime very slightly. The recipe is a pretty good grapefruit, but I think it needs some 'x' factor to really pop. In the meantime, though, this is probably my favorite flavor. So I may never change it that way.

v1.1
cactus 1.5
key lime .5
lychee 1
orange cream 4
pink guava 1.25
watermelon 3

notes: good. Adding mango for shits and giggles. "Tropical grapefruit"... yum? The progress with this recipe is inspiring me to make my first 300mL. Will update with how that went.

v1.2
cactus 1.5
key lime .5
lychee 1
mango .75
orange cream 4
pink guava 1.25
watermelon 3

notes: Mango was a good addition. Any adjustments to the recipe these days are just mental masturbation, as it's really good regardless. Mango does make the mix a little sweeter perhaps than I'd like, so I'd like to play with something with a little tartness or bitterness. Maybe cranberry? Maybe more lime? We'll see. Also the 300mL bottle accelerates steeping while prolonging the amount of time the juice exists, so for the first time I was able to detect that over time, the orange cream will begin to overtake the mix. I'll tone it down slightly in the next one. So just for shits and giggles: slightly decrease watermelon, orange cream and cactus, remove mango, add cranberry. I know that sounds drastic but I don't think it will be.

v1.3

Cactus 1.25
Cranberry .25
Key Lime .5
Lychee 1
Orange Cream 3
Pink Guava 1.25
Watermelon 2.5

have yet to mix this up, but looking forward to it