My only concern with FF combat system right now is the GCD a tad bit too high (2.0 would be perfect imo) and the permanent moon walking and omnipresent lag.
I can live with the GCD issue, but god that this constant lag is irritating. Even WoW vanilla didn't have such issue so how come a recentgame like this one can't fix it?

See everyone moonwalking, dashing every now and then is really annoying. Boss mechanic make it worse as I fail to count the amount of time I've seen myself or other player get hit by aoe that their clearly left. I mean, even the body is far from the original explosion location. It's also rather fun that we can go within an aoe and get 0 dmg because it takes almost an entire second for the server to react to our movement.

I'd like to point that I've absolutely zero latency issue in WoW or any other game. And it's not even latency in itself, it's just how the game handle data packet.
I don't remember where I read it but FF14 send packet less often than WoW and most other games, which explain the constant moon walking and feeling of lag.

I really hope that they'll fix this for 4.0 because I'm not sure I'll handle another expansion with a sluggish gameplay. This is a shame because so many things are good about this game, unfortunately, "combat" is a pretty core thing.