Right now, we can't be sure how dual wielding will be balanced in comparison to other combat options, it's not something Bethesda has done in the previous games in the series, which already had some balance issues, so I can understand being concerned that dual wielding might not be balanced that well, it's not the first time I've seen such concerns on the forums, though the last time, the poster was concerned that dual wielding might not be worth using at all, but in the end, we'll just have to wait, and see what happens.
Hopefully, Bethesda can ensure that dual wielding is an option that's worth considering, but won't overshadow other options.
I'm more worried about if it will take away from people who wish to single wield one handed weapons.
What if I just want to use a Short sword and nothing in one hand and focus with just that weapon?
That's a pretty good question, we know we can dual wield, or use a one handed weapon with a shield, but what about just using a one handed weapon without anything in the other hand? It could well be that there will really be no benefit to doing so, a problem which past games had too, honestly, it's nice that dual wielding provides an alternative for players who want to use one handed weapons but don't want to use a shield, but it still doesn't adress specifically what players who want one weapon and only one should do. My suggestion would be to give some sort of bonus only available when using one handed weapons with nothing in the off hand, but I'm not sure what the best option would be for that.