Hi Janssen and welcome to Simply discus .
Your tank size and your described visual image , looks very promising right from the start .
Its good that you have already read many articles and watched videos on discus before you decided to take the plunge.
My advices on your two questions .
All the domestic strains are equally demanding to keep .Wilds are known as something for a little more experienced discus keepers , other than that domestics are all the same .
Whatever you decide to feed them I would advise for variety in foods and bigger time frame between first and last meal especially for juvies.
What size/ age discus do you plan to purchase ?
Another advice would be for your WC regime .
25% a week is very minimal for discus . Maybe you will GET AWAY with 10 adults on this WC regime , but if you decide to buy and grow 16 youngs and feed them beefheart multiple times a day I'm afraid that 25% weekly would not suffice .
I will start at least with 50% biweekly for the first months and adjust it from there accordingly.
Good luck and please send some photos of your tank and discus when you are all set and ready .