The length of the weapons didn't actually make a difference.
You had to be the same distance to hit something with a claymore as you did to hit it with a dagger.
So I don't really miss it since it didn't add anything other than visual flair.
The proper thing to do would have been to make the weapons different in practice rather than to simply scrap options. That's actually been a recurring trend in Bethesda's decision-making. Look at Mysticism; it was stretched thin in Oblivion thanks to the removal of a lot of effects from Morrowind (detect key/enchant, Mark/Recall, interventions, moving absorb effects to restoration) and then Bethesda said "Well people mostly just use it for 3 spells now anyway so let's just scrap Mysticism and move those 3 spells into other schools". A better solution would have been to help bring Mysticism back to being on par with other schools rather than to just remove it.
Same thing with the shortsword/longsword ordeal. Rather than remove them because the difference was only aesthetic, why not put some more fine tuning in to make the differences more clear cut? It wouldn't have even taken a lot to do, seeing as how most players would probably be satisfied with a difference in weapon damage, attack reach, and swing speed.