Atm there are already 14 sites connected to "Big Waterfalls". Possible further entries that come to my mind are e.g. Kaieteur & Niagara. But do they or others add any OUV to this connection the inscribed ones still missing? I can't find any. IMO it's sufficient.
To be fair - of the 14 WHS with a "Big Waterfall" Connection, only 2 waterfalls, Iguassu (inscribed twice by different countries) and Mosi-oa-Tunya (Victoria) are inscribed "solely" because of their waterfalls. Of the other 11 - I don't think any of them would not have been inscribed if the Waterfall concerned had not been present - even Canaima fully justifies inscription because of the Tepuis with or without Angel Falls.
We have discussed Kaitetur before on this forum.
You may care to read up this
from 2009. Unfortunately the link I found that long ago which gave a history of the attempt to gain inscription at that date is broken.This
from 2012 gave extra information to that date.
Since then of course Guyana has removed the site from its T List altogether. Whether because it received clear indication that it would never gain inscription .. or because it got fed up with UNESCO/IUCN's attitude towards it .... or because it came to the view that countries like Guyana are unfairly penalised by the rest of the World who want them to maintain their natural respources (i.e forests) in pristine condition without compensating them for doing so and that they might just as well therefore capitalise on those assets I know not.
I would fully expect that the area around Kaieteur will become badly compromised by logging and gold mining
etc The sheer stupidity of IUCN/UNESCO in not inscribing the site when it had the chance and giving Guyana some positive strokes (as well as gaining some "leverage" in dealing with Guyana) will then be seen for what it was. When other small countries are given a degree of "license" to help them gain a first inscription that was noticeably lacking in the case of Guyana. To alter an English quotation ...."For the sake of a few extra hectares the forest was lost".
You will gather that I believe that Kaieteur should have been (and should still be) inscribed.......with or without much of its surrounding forest. At least if it is "inside" the UNESCO tent there might be more chance of getting Guyana to make an extension. And the WH scheme is, after all, primarily supposed to be about "protection". The fact that IUCN was prepared to countenance inscription with more land would indicate that IUCN wasn't of the view that the Surinam inscription adequately covered the OUV of the Guyana Shield area. Regarding the "scenic" merits of the Falls - I see Wiki claims them to be the "World's largest single drop falls by volume of water"- but, in most size comparison criteria they don't match Iguassu or Victoria. However, they are pretty amazing. If I had to put all the major waterfalls I have seen (which include most of those "connected" plus others not inscribed) in sequence they would come 4th after Vic Falls, Iguassu, Angel....but, not by much!!! The "List" should have room for all of them - certainly well well ahead of much of the other dross which has been inscribed!
Just looking at the inscription criteria for each of Iguassu and Vic Falls
Iguassu - Cit vii (size etc) and Crit x (ecology of area)
Vic Falls - Crit vii (size etc) and Crit viii (geology)
In both cases the second criterion chosem seems to me to posess a somewhat "thin" argument and we can assume that Crit vii was paramount in both cases. Kaieteur could have been given the same treatment IMO.
Niagara is a different matter - "Waterfalls sitting inside a Tourist theme park very messed around by hydro schemes" just about says it all for me.