Here is a sucess story .....
I've had a flower male for 5 years now. The males stay smaller he's around 16" across and 18" long there disc are shaped like an egg. As for compatibility. I left mine on his own for many years. Now he is a furious eating ray and eats fast and pounds food hard. I would not trust a my flower around new born pups he is really attracted to live foods .they typically are not good with other rays like Leo's and motoro type but can be mixed with certain not so aggressive ones. All rays act different so I can't say much about mines behaviour being the normal for flower/tiger rays. They are very difficult to get in and in decent shape. Have to use RO for a while to get him used to your water. For the most part they are amoung the hardest ray to keep alive. I've had others that died instant or after few months. It's very hard to find a long term captive specimen in North America . I'm one of the lucky ones. Mine is pretty tough now I think it just has to be well cared for and it will come around and mix with any rays. But it will be impossible to raise them up with other types in the tank it does take them quite some Time to start feeding fast like others