Is the game really going to have a GCD system?

[Reynhart]

The problem with such a long GCD without independent ability cooldowns is that you have no reason to use anything aside from your strongest attack every single time.

Yes, no reason.
Except:
- Cost reason. We should assume that stronger WS will cost more TP than weaker ones, so if you need a quick hit with what TP left you have, go for it.
- Additionnal effect reason. Several WS have a little bonus that you'll need. Like an enmity boost, a bleeding, flash or stun effect.
- Radius reason. WAR won't spam Steel Cyclone over and over, because you don't always need an AoE WS.
- Combo reason. Every combo starts with an early WS (Probably a weak one), so you'll use them at least to pull off the entire combo. And for "why using combo", see the "Additionnal effect reason".
- Break reason. WS can still break parts on bigger mobs, regardless of their damage output. They should design combat strategy based on breaking the right parts.

I think that's a bunch of good reasons already but we could imagine others too, like...
- "Skillchain" reason. We know "battle regiments" are still on the to-do list. They'll probably use some of our WS that could be deemed as "useless"