For the Katana: it only does 36 cut damage. There are 1h that do similar damage. I know you hate to hear this phrase, but it is plenty valid: Katana's don't have the luxury to use a shield.
It has speed, it has mediocre reach, but its damage is on the lower side and it can't use a shield. It doesn't exceed in all areas.
Turning into a swing does give you a slight speed benefit, but the last major patch of warband added sweet spots, making this less of an issue. People who are aware of this technique tend to overestimate the speed benefit it gives. Also, most people aren't aware of this either, but you get the same speed benefit regardless of the size of the weapon, but it is much more difficult to do with a shorter weapon.
The converted skill points into stat points I will hand to you, but there is certainly a major trade off for that: the infantry 2h user becomes much more vulnerable to arrows. On my characters that use a two handed weapon (either polearm or 2h skill) I still put points into shield so I can carry one on my back in the event I need to use it for archer cover. Also, the additional stat points converted would at most be between 2-5 extra stat points... which translates to 1%-2.5% faster. If you are using a German Greatsword (formerly pike of tears) that would translate into an effective speed of 95 at most.
I hate to hear it. 36 cut is plenty, no 1h reach that much.
It have speed, more true reach than most of 1h, damage is decent enough, can be used with shield against archers. Its's quite good, very good actually.
I know about it, thing is, it's still very helpful. Higher damage of 2h partially offset sweet spots. Also, 2h have more efficient stabs that deal more damage on average thanks to superior animation (on the other hand, 1h have nice left swing that nicely fit with opponent's head, but is quite short).
If we want to argue about greatswords, fine, just keep in mind that those have awesome damage that allow them to even more avoid sweet spots and inflict decent stun, so effective speed in melee (if greatsword user is capable and strike first) is higher (keep in mind that shield slow down 1h feinting, making it easier to block, and harm footwork, making it hard to position yourself well).
Still, my suggestion was not about increasing maximum speed for 1h class, it was rather meant to bring more variety to the character builds, and make mid-tier, and high-tier normal reach 1h a decent weapons that are not so much worse than side sword that have 101 speed (it's rather high value for such flimsy weapon that deal so much damage)