(1) monitors vs. floorstanders
(2) Focal vs. Dynaudio
(3) price range
RE: (1) monitors vs. floorstanders. IME, it is usually easier to integrate a pair of monitors with a sub than a pair of floorstanders, and the results with monitors + sub tend to be more coherent than floorstanders + sub. On the other hand, floorstanders are likely to give you a greater sense of scale. So which is more important, scale or coherence? It depends on your personal preferences and what kind of music you tend to listen to. Jazz? Chamber music? Go with coherence. Rock? Symphonic music? Go with scale. IMO, of course.
RE: (2) Focal vs. Dynaudio. I've owned multiple speakers from both Focal and Dynaudio, including two speakers that bear some resemblance to what you're considering: Focal 1007be and Dynaudio Focus 140. Incidentally, I also have a similar sub: JL Audio Fathom 113. And I've heard the Diablos, but not the Focus 380's.
The Diablos, and Focal speakers in general, are resolving, transparent, and coherent. The Dynaudio Focus line is dynamic, warm, and relaxed. Which is preferable is a matter of taste and what the electronics are like. With the wrong electronics, the Focals can have some glare and grain. With the right electronics, they can be very realistic. I don't have much experience with Classe or Bryston, so I can't be of much help as to how well each of those would mate with Focal and Dynaudio, respectively.
RE: (3) price range. Again, totally up to you. I only mention it because at the moment you seem to be comparing apples to oranges in terms of price, and IMO that can confuse the matter.
Hope this helps a little.