Sony might try switching between different European game conferences and I like that fans from more countries will be able to experience a show like this and that developers will be able to reveal their work in their own countries e.g. at Paris Games Week 2015 with Detroit: Become Human (French), Wild (French), Gran Turismo Sport's collaboration with FiA (French), Uncharted 4 MP presented by Christophe Balestra (French), etc.
I can't remember the source but iirc I recently read that they might attend a game conference in UK, Italy or Spain so maybe:
2014: Germany (Gamescom)
2015: France (Paris Games Week)
2016: UK (London Games Festival)
2017: Spain
2018: Italy
2019: Germany
etc.
I just hope they attend Gamescom again as it's only a 7 hours drive/3 hours flight from where I live in Denmark.
Besides, the German audience is just a bit better at creating a great atmosphere (no offence to our French users). The audience was so unimpressed no matter what got announced at the PGW 2015 PS conference XD
