Relative component value to overall SQ.

The speaker-room interaction is the most important, but that does not necessarily mean it will cost the most. A small listening room with nasty bass nodes may benefit from a small stand mounted speaker/monitor considerably cheaper than a speaker required to fill a larger more neutral room. So I agree that it is so difficult to generalise.

Also to a newbie I would seriously recommend looking at active speakers with built-in amplification. Then simply add a source/pre-amp combo.
The ATC room at Munich had their £3k cd/DAC/pre playing into their active speakers and it sounded a dream - a one box solution with 80% of the cost being on the speaker. Definitely worth considering for a first-timer.

What I don’t understand is why the OP would ignore the source? Are you assuming all sources are equal?You can’t assume a perfect signal from any source. In the 1990s in the UK the general advice was to spend 50% on the source. These days I rarely hear that but nevertheless I would recommend certainly spending as much on the source as on amplification.

In summary, and with caveats explained in the first paragraph, I would say to a new Hi-Fi enthusiast seeking advice:

Trad system
Single source (including DAC): 20%
integrated amp: 20%
speakers: 50%
cables/rack/isolators: 10%

active system
source/dac/pre amp combo: 25%
active speakers: 65%
cables/rack/isolators: 10%

If affordable and within the budget active speakers with dsp or a preamp with dsp would help solve room issues without treatment. And treatment is demanding on your space in terms of size (bass traps) and decor, so dsp would be easier for a new hifi enthusiast to deal with.

@elizabeth On the role of room acoustics as related to this topic, I would encourage @N80 and others that for a beginner it doesn't have to be complex and in some ways, you don't even "need to know what to listen for".
Most beginners choose dynamic (cone driver) speakers and they almost all emit sound at wide angles that result in sound reflecting off the side walls that hurt sound quality. Doesn't matter if we are talking floorstanders or monitors on stands, they all do it, mainly from tweeters & midrange drivers. Absorptive panels at the first & second reflection points, will almost certainly reduce echo and improve clarity of vocals and higher pitch instruments. Inexpensive options like these
https://mioculture.com/shop/wall-ceiling-tiles/acoustic-weave-paperforms-white
or DIY homemade alternatives made of Owen's Corning fiberglass from the local hardware store are worthy of consideration.
Absorption of floor reflections with a natural Fibre rug between seat & speakers almost always help, especially when dealing with hard flooring of tile or wood, but also with synthetic carpet.
Glass windows are super reflective and natural fibre heavy upholstered curtains will tame them every time.
By playing a test tone CD of varying frequencies one can easily identify bass interactions with the room. Many rooms inherently have certain frequencies that play too loud(peaks) and others not loud enough (dips). The extent of those anomalies will be an indication of if bass traps in the corners behind the speakers would be a help or not. Fixing bass issues is sometimes pretty tricky, but I am confident that you will get the point. 
I find it frustrating when folks spend big bucks on gear, ignore the room issues and later lose enthusiasm for the hobby, because they aren't drawn to the music playing on their system. Rooms need to be conquered and it's not that hard nor expensive to do so.
While a DSP approach might be an alternative, I  have always been leary of adding more cables and boxes, as the chance of noise and grounding problems increases. Perhaps newer DSP solutions exist that surpass what I have heard. Cheers,
Spencer 

It's a fact that you can take the average cost of people's systems and discover their percentage shares of total cost. What are those shares of systems that people claim to be happy with? Maybe there's high standard errors, but those means do exist and could be found with a survey. What do experienced audiophiles think that those shares are?

That's how I understand the OPs question. 

Of course the next issue is that you may have 4k to spend on a system now but have 2k more in a few years. In that case, the shares will be difference seeing as you can't upgrade each piece with 2k.