Interesting topic.
1) Box and papers. It is really hard for me to see the appeal of these items for a Replica. I would not be 100% sure to label all the people willing to have full boxes and papers scammers, as someone might simply like to replicate the feeling of fulled out purchase. To summarize: I agree with you: I find very difficult to justify the existence of these products, but people have different tastes.
2) Movements. If caseback is open and movements are fully replicated and egraved, they are great to see. Also, it is important that these movements often are able to accept genuine hands/dials/datewheel. Sometimes is also a matter of dimensions.
You don't like Frankens, but this is a huge factor.
3) Franken. Here I strongly disagree. I agree that 4-6000€ Franken Submariner are silly (since for 7500€ you can acquire a Genuine wihout B&P), but spening 300-1000€ to correct the major issue with a Replica might be something I can get behind.
For Daytonas, for example, Dials to me are quite bad. Until few months ago, GEN dials could be found well below 1000€. It changed the aspect of the Wach in a huge way.
1500-2000€ Daytona Franken are extremely close to genuine and a real pleasure to watch/wear. 3000€-4000€ (ones with gen hands and bezel) are very expensive, and I'm hesitant to consider them good deals, but they are still 5-6 times cheaper than a genuine and consider that 80% of visible watch is genuine.
4) 904 issue: here I strongly disagree. Not only a correct metal is mandatory, but I'm also hesitant to accpet as true that the 904 used on Replicas is the same as Steel from Rolex (or 316 for other brands). The truth is that Genuine always look more shiny and precious.
My gen Daytona looks almost white gold. steel is very "white".
My replicas of Audemar's RO look grey and look more like they are made of iron than steel.
Maybe it is a matter of brushing, but this is something I have rarely seen discussed here.
the reason people wear replicas is various, and impossible to agree on which is correct (since many of them might be correct since people are different). Some people are OK with 50-60% accuracy (DHGate for example), come people are ok with 90% accuracy (and like to buy OOTB replicas of major factory).
Some people might want to eliminate differences too visible and go light/heavy MOD.
It is also a matter of what model you want and how much are you ok to lower your limit of tollerance.
Speacking of me:
I'm very addicted to good dials.
I would like to have a Nautilus (and not a white one, since I already have 3 white watches)
I had to give up. Dials form all factories simply are not even close to genuine colour. If they had to make a blue dial this far from original, they could do a red/yellow one.
No one knowing what a Nautilus is could consider it similar.
Maybe PPF / PF blue are beautiful. But PatekF dial is simply different.
Genuine one goes for 5-6000€ (and I would not trust seller), but if a genuine Blue Nautilus dial costed 1000€ I would pull the trigger.