It is very important to know who made this list. (Not just to be able to flame him.) This question also coheres with the reason why iMTG's list is probably much better and especially more objective.
There was a group of five very different persons. Pros, casuals, speedrunners, people who play everything, people who play only the best maps, and so on. Then we made a voting where every one could rate a map with "Yes", "No" and "Maybe". Following the results of this voting we got a list of maps which potentially could be selected maps and which aren't really popular at all.
After we got this first overview we discussed every single map (also maps without a good voting result) in the group, people could explain why a map should be selected or why it shouldn't. We took a look on statistics such as finishes, we talked about the general recognition of a map (e.g. if people are still talking about it after some time), we observed whether maps are still played and so on. Combining all these elements of subjective and objective reasons we made up a final list of selected maps.
Of course, such a list is never perfect. You can allways discuss about single entrys. But the way we have choosen the maps we could be sure that most of the list is consistent and understandable. We could be sure that the probability to miss any real good map or to add a crap map is low enough. Surely it would be still possible to add/remove maps to/from the list if another community member proposes a map followed by well made arguments.
While in our list such failures would be a real minority, the current lists contain quite some maps which are highly questionable.
I guess the reason for this is based on who made the list, e.g. if it has been made by only a single person then it surely is less consistent than a list made by a group of different people. Anyway as I said: I don't know who made it and thus I can only assume something here, that's why I asked you who made it, so that we can discuss on facts instead of assumptions.
Since you wanted suggestions I will repost iMTG's list here. Keep in mind that this was made in summer 2015, so maps released later aren't considered.
Camouflage by Meliodafu
Gold Mine by <BµmM>
Hoo! by TyxpekCZ
Houll by Evoli
Icebreaker by AKc0RiZer
Introduction by Themix
Just2Easy by [A] Awesome
Kindergarten by Silex
Kobra by Zerodin
Kobra 2 by Zerodin
Light Grey by Lightbulb & ٭ıƞdex'<3
Planet Mars by Aoe
Planet Venus by Aoe & Knight :3
Thor by Ama
These are 14 maps out of 98 maps released back then. There is a good variety of different difficulties, types of maps and mappers. If there is a series of maps then not more than 2 maps per series were chosen.
Now let's compare this with the current list:
Bullets by Meliodafu (2016)
Camouflage by Meliodafu
Cartoon by fikmesån & Im 'corneum (2016)
Goo! by TyxpekCZ (late summer 2015)
Hoo! by TyxpekCZ
Icebreaker by AKc0RiZer
Introduction by Themix
Kobra by Zerodin
Kobra 2 by Zerodin
Kobra 3 by Zerodin
Kobra 4 by Zerodin (late summer 2015)
Planet Mars by Aoe
Planet Venus by Aoe & Knight :3
Tiny Tandem by timakro
(The maps which have a date in brackets have been released after iMTG's list has been made.)
There are also 14 maps out of 121 maps in total. There are less easy maps, less mappers, less variety, but instead 4 times Kobra and maps such as Bullets or Cartoon which aren't good enough on an objective base.
We also started to do the list for Moderate, but never finished it. These are the maps we had chosen so far, keep in mind: It wasn't finished. Anyway it should give a small picture of what kind of maps we were to add to the list of selected maps.
Boo! by TyxpekCZ
Caventure by Meliodafu
DayDrive by BlaGK
Jumanji by Avaron & Rashu
Neverwhere by Bixes & Themix
Red Avenue by Bixes
Samsara by Meliodafu
SunDay by Gridwyn
The Trip by Hindu
As you can see, here we also provided a wide variety of different maps, mappers, styles, difficultys and so on. If we would have finished this list we probably would have ended up with about 20 - maybe 25 - maps out of around 200 maps which have been released back then.
To sum this up:
I would never say that iMTG's list is the perfect list everyone has to agree with. Although, the complex and time-consuming method we used to elect the selected maps provided a much more consistent and diversified set of maps.