For sure these three
Trimac for the spots
Midas/Red Devil nuchal hump
Synspilim (sp?) nuchal hump and red throat/head
Also possibilities
Festae Cichlid (red terror) brilliant red color and stripes
Texas cichlid irridescent spots
Jack Dempsey irridescent spots
Severum (i'd leave them out)
Red parrot (i'd leave them out too)
Not that I've bred these, but if I were going to I'd first cross a Trimac and Synspilim, Trimac and Festae, and Midas and JD, and Midas and Texan. (I'd leave the Severum out of the mix).
I've seen a lot of suppossed Flowerhorns that were way to heavy on the Trimac side and basically look just like a trimac without the pizzazz of a top quality flowerhorn.
Next I'd cross a Trimac/Synspilim with Midas/JD and also cross the Trimac/Festae with Midas/Texan.
Next I'd cross the offspring of the above with one another. At this point you'd have 25% Trimac, 12.5% Synspilim, 25% Midas, 12.5% Festae, 12.5% JD, 12.5% Texan. The off spring of this I would then cross with a 50/50 Trimac/Symspilim hybrid. And voila!!! That's the Flowerhorn that I would breed.
Ultimately, in my opinion, you have to have Trimac which is obvious and Synspilim for the hump and red throat/head. Midas helps with the hump and then Texan and JD are for the dazzling blue scales. Festae, Severum, Red Parrott are in my opinion optional for some extra (potential) flash. After you cross all these, then it's time to pray to the Good Lord that you attempts to be Dr. Frankenstein and create the Ultimate Frankenfish pay off... By the way, be sure to have some hungry full grown cichlids to eat the low quality off spring. There is nothing worse than buying a flowerhorn and having it grow up to look just like a trimac or any of the other cross bred fish in this monster.