Hi
@SpectacularFish - sounds promising so far! Your observations are very much in line with my expectations, which is always a relief for me as an audio reviewer.
Re: sounding less dramatic and fun than your Arias, I believe this is the Focal sound signature of adding a bit of boost in the presence region and lower midrange to make everything "pop" a bit more. This works well particularly if you don't have a very high-resolution amp/front-end, it is a bit of equalization that restores some lost presence and detail. Many people love this and it works very well for many systems and musical tastes; I listen almost entirely to acoustical classical music and it works less well for me, particularly with the type of electronics I prefer.
With a better amp, you will simply get more of the music. More detail, more space, more dynamics, more nuance, more rhythm. But I will call out 3 areas that matter to me a lot, and which I find you can continuously upgrade in a stereo in the unending search for realism.
First, "micro" dynamics. People associate dynamics with power, signal-to-noise and extreme swings between loud and soft. I think what is much more relevant to musical enjoyment are the subtle changes in amplitude that bring out all the subtle twists and turns of a phrase, the ebb and flow of intensity of a song and the pulse of a beat. This is the area where I find the amp often makes more of a difference than the speakers. I once put a modified Rega Brio amp on my friend's $90 Sony bookshelf speakers mounted on a wall connected with 20 ft of monster cable. He thought it was a waste of time, and swore his Sony receiver was awesome and the speakers were the limiting factor. His jaw quite literally dropped when I started playing music on the Brio - all of a sudden everything came alive with energy, not just loud and soft but musical lines sounded more expressive and just sung out. Even with the crappy speakers! You cannot get this without a great front-end/amp no matter how amazing your speakers are. I have found this area continue to improve in my system as I have gone from $300 to $3000 to $30k amplifiers.
Second, the area which I guess I will call "tonal colors" or "harmonic resolution" - the ability to preserve the complex and distinct harmonic signature of an instrument or voice. Most gear will gloss over the overtones of an oboe, the resonance of a soprano, the varying timbres of different strings (I'm a violinist, my wife is an oboist). Yes, you can still recognize the sound of Yo-Yo Ma or Ella Fitzgerald or a Steinway piano on most any decent audio system these days thanks to the very low distortion and noise of even the most common device e.g. an iPhone. But there is another level of beauty and palpability to their unique tones that can be unlocked with a higher resolution system - the shimmer and vibrato of a delicate passage, the rich overtones of a piano's lower registers, the brilliance of a piccolo in an orchestra. And again, speakers cannot recover what has been lost upstream in the amplifier. These sort of nuances honestly may not matter to a lot of listeners, particularly those who haven't had a lot of exposure to live acoustic music, which is why I think you start to see a lot of divergence of opinion whether high-end gear, cables, etc. are "worth it" - it's in these types of subtleties. But that is one of the things it is often necessary to pay more for. Some people also refer to this as midrange "rightness" or "completeness" - I think it's more about the harmonics and it's because the ear is most sensitive to midrange harmonics (and most of the music is in the midrange) that you hear this the most there.
Lastly, frequency extremes. On the low end, it usually takes strong, clean, low-impedance power supplies to deliver proper bass that has tone, impact and clarity. You can tune a component to have a richer, fuller bass, at the risk of making it sound flabby or boomy; you can tune it to have extremely tight, clear bass, at the risk of sounding lean and hollow. It usually takes higher-end amps to get both without compromising one another, and even with the mega-buck gear it becomes a matter of taste. At the other end, treble is where the ear is really sensitive and this is often where people hear the most qualitative differences between amps. There are many factors - noise, power supply quality again, circuit stability, frequency response, etc. - but in the end just as in the bass, it comes down to delivering all the signal without some compromise. E.g. I find Rega and Naim gear to have a softer top end that sounds very pleasant, but a bit "closed" and losing some fine resolution. Many other amps have extremely clear treble but with a trace of harshness that can get fatiguing. The great amps will give you detail and extension and openness while sounding smooth, natural and alluring. This is where often it is more about finding the right balance for your system and ears than spending a lot of money - you can buy a $40k amp for your Focals or Dynaudios but if the balance isn't complementary, it won't sound right.
Anyway, that is my $.02 - all those words are meaningless compared to just getting a nice amp in your system and hearing the difference, but hopefully that gives you something to be excited about.