I'd like to see a simple one hand grip long sword with a symmetrical point and double edged with a cross bar hilt. I.e. what many would consider a basic long sword.
All the long swords in game have something odd about them, they have a massive grip that looks stupid specially when used one handed, they are jagged, have a bizarre hilt or the blade has to look more like a shovel than a blade etc etc. It seems no motif has jet to say you know what lets keep it simple symmetrical and proportionate, instead we see the worst fantasy weapons have to offer where the sword will have the aerodynamics of a club and completely impractical in design.
Now that we have Augur that talks to us... I'd like an "Intelligent Sword". It would have to be limited to commentary as we travel through the world. That's a lot of location specific dialog, so I certainly don't expect they will ever do anything like this.
Make it look like a Moorcock runeblade. A black bladed weapon covered with strange runes carved deep into its blade.