First of all let me start with this to be clear:
THIS IS JUST SPECULATION, I HAVE NO SOURCE (OR CLAIM TO) INSIDE BLIZZARD OR ANYWHERE ELSE, SO DON'T ASSUME I'M CLAIMING A FACT OR WHATEVER!
Ok, that said, let's move on with the topic.
Blizzard has stated they'll be exploring a new gearing up system in 5.4 but aren't ready to talk about it, so I'm gonna try a guess!
War Effort Point System - Since Valor gear will be gone, from what I understand, this new system will replace it. You'll get a currency, I'm calling it War Effort Points (WEP), that you earn every time you do a dynamic event, quest or kill a raid boss. After a certain threshold of WEP you're allowed to choose loot from some sort of interface or vendor. With the introduction of dynamic events, unless WEP were capped, you could arguably get limitless points by just grinding dynamic events that, I suppose, will be an evolved version of the 5.3 events:
- Steal/poison/damage supplies;
- Kill loyalist officers;
- Sabotage defenses and siege machines;
- Plant bombs;
- Steal plans;
- Retrieve information;
- Set up traps that react on and kill enemy NPCs;
- Snipe enemies (using the same type of interface of that sniping quest in Jade Forest);
- Gather tids and bits (like Alterac Valley) to empower certain weapons, wards, elementals, etc;
- Spy on the other faction so you know they won't be backstabbing you;
etc
Similarly, the WEP system could also include a Ranking system, which you gain after certain WEP thresholds as a way to gate which gear you can get. Ranks could be limited by a weekly cap or stage progress à la Isle of Thunder.
Attaining a certain rank could also allow you to unlock an extra boss in the raid (normal/heroic difficulties) which would be a nice addition, imo.
Once again, it's just speculation so take it with a grain of salt and give me your thoughts .