OK, let me throw some theory out there for consumption.
You may read this and eschew or toss it out the window
Speakers are rated at a particular operating range and max power.
In case of ELAC Debut 2F6.2, the sensitivity is 87dB and max rating is 140W.
This tells me that the max SPL possible by this speaker is about 108dB.
This is 108dB at 1 meter at max power rating.
Typically one would need an SPL of 80-90 dB for music listening at seating position.
So you are covered in this aspect from a speaker point of view.
80-90dB, in my opinion, is quite loud, but your ear/room experience may be different.
Ideally, a speaker operating below its 60-70% of max SPL is a happy one.
The LF driver excursion (start/stop) is well controlled, etc, etc.
In theory, these ELACs may need 25-50W of clean power to shine and excel.
Now coming to the power amplification part.
Amps are quite happy when they are not pushed beyond 50-60% of their rated power during continuous listening.
Peaks are different; a speaker nominally loading an amp at say 30-40W and occasionally demanding 50-60W is normal.
When driven hard, amps become unhappy, heat up, cause distortion, clip, etc, etc.
Clipping is dangerous, as it can damage LF drivers and tweeters in speakers.
When clipping occurs, woofers will complain audibly, tweeters will silently die.
I have not personally heard out the speakers selected by you, so can't comment on its behavior.
If I were to choose a stereo amp or an AVR, I would look for a power capability in the range of 50-80Wpc minimum.
Reason being, if an amp can do, say 80W max, it will behave reasonably well in the 25-50W nominal operating range.
Stereo amps usually specify what they can support at 8 ohm and 4 ohm loads, full frequency range
AVRs usually specify only 8 ohm loads, full frequency range.
ELACs are 6 ohm nominal, don't know minimum.
FMs who own these towers can chime in with better understanding of matching amps/AVRs.
Cheers,
Raghu