Quote: "One day, all the problems of FPSC (no save/load game, no flashlights, no vehicles, no friendly AI etc) will have been adressed"
You cant sy that - no one knows that what if any improvements will ever be made - you just have to get on with game making with it or not at using it as is or not. You cant rely on any improvements until they are a reality.
The truth is FPSC is very inflexible, full of instabilities, bugs and issues.
You can make some simple dungeon crawler types of game with it but not a serious, professional type game requireing modern functions and features which it lacks, nor games which require large outdoor areas due to problems with culling, lagg, AI and slow engine speeds.
If you are attempting any kind of modern gamemaking you will have major problems to overcome and yes the inflexibilities of the engine system.