UrbanDev, you're painting a rather bleak (but rather amusing because I can well imagine it!) version of what might well happen in this area.
Who knows what will happen in a development like this? Almost all of the important variables are unknown, yet the price of this development is not cheap by any stretch of the imagination.
In my opinion, what is likely is that prestigious restaurants and shops will go nowhere near the Corvin Promenade. High-end retailers won't even set up on Vaci utca, much less District VIII! The entire Korut is still a no-go area for most Western retailers and restaurants. If you could drop into the Corvin Project from the air, that would be one thing, but at the minute, it seems more likely that you would have to enter it from either of the main entrances at Klinikak or Ferenc Korut.
Further to this, upper-end restaurants are likely to continue to locate themselves alongside the new Gucci, Burberry, etc. on Andrassy Ut or in or close to other similarly prestigious areas of the city. Why would they take the risk of setting up in a high-rise, office-centred block in VIII.
I agree with UrbanDev, Dodala. Forget the 3D rendering. Ask the developer what retailers and restaurants they have signed up. What businesses will locate here?