Love all of them, they all have potential. For the white, you got your picture, get in there and remove the flowers. The tree is freshly repotted and needs to put energy into roots.
Purists will tell you for quickest development, you should not let them flower at all. In my mind what is the point of an azalea if you don't let it flower.
However, on consideration, and after watching mine for the last decade, I do agree that flowers are a big metabolic cost to the plant. The energy that goes into flowering is significant. For best growth, especially the season after repotting, don't let more than a few flowers develop. If possible, in autumn, before the azalea has put a lot of energy into new flower buds, go through and prune out the majority of them. You can leave a few, after all, that is the point of azalea, but leaving too many flowers will slow development of roots, branches and the rest of the tree. Especially since you just repotted this one, cut the flowers off now that you have your photo.
It has taken me years to accept this, but now I do go through and remove buds on azaleas in early phases of development.
Remember, as you create your branch structure, leave room for flowers. The branches should be platforms for flower display. Your whie has very large flowers, leave enough room between levels of branches so flowers have room to expand and develop.
But you have been doing bonsai for quite a while, you probably already know this. But for those new to azaleas, that is what I would advise.