Yeh, both don't need changing. I've used both since the patch (kind of sad how its become so increasingly popular especially in recent weeks) because theya re the closest thing in the 2hed sword category that resembles a sarranid/middle-eastern weapon. They both are very good weapons and don't need rebalancing, a masterwork dadao has 94 speed with 47 cut. Theya re faster but slightly shorter 2hers and are well balanced considering their higher than normal damage with no stab. And please dont add a stab, there are way to many 2hers that use the lolstab to do well its nice to have some that are just normal hack and slash style swords, if anything remove the katana stab that only does like 19 damage anyway.
If anything during the middle ages most people in battle didn't use stabs as the metal working to make a point sharp took a lot more effort than just a simple sides given edges. Its actually pretty unrealistic how many of the wepaons in cRPG have great stabs as only by the romans and then later in fencing that swords were heavily utilized for stabs. During most of the middle ages swords were slashing and hacking weapons, but in cRPG you see all these people dancing around doing lolstabs because it racks up kills. Most of the swords should have their pierce damage on the stab cut in half as they have lolstab and the fact that the stab is the fastest of the 3 swings (side, overhead, thrust). Would make stab less overused and cut the issues with excess range people complain about as the longest reaching swing wouldn't also be the most damaging and the most abusable with lolstab.