My bottom 5:
1. No female legionnaires (that aren't essential to the story)
Had it been an all male army I would not have had any problem with it, but as the two only officers outside of Tullius who have anything to do with the storyline(s) are women and we hear tails of women running off to join the imperial army it just doesn't make sense. At least you can find the corpses of some female imperial soldiers, maybe they are just really incompetent and dies before you get the chance to meet them.

Also, all male guards make for a blander city.
2. Tiny Cities compared to claims/overall population
Of course most of this comes from just overthinking things, but where do all the nord soldiers(on both sides) come from? Same can be asked of the hunters, farmers, bandits and essentially everyone else you meet on the roads. Did every family in Skyrim have like 6 children, giving just one of them the house while everyone else becomes wanderers? And where are the farms of the random farmers you encounter? The guy who (try to) sacriface his cow in order to keep the giants away from his livestock ... Where is his livestock?
Ivarstad is probably the most annoying example. One of the residents say that everybody moved away, but did they take their houses with them? Or did everybody sleep on bed rolls at the inn? There are currently three houses(one in ruin), a sawmill and an inn in Ivarstad - there's not a single sign of anything else ever being there.
3. No magicka damage scaling
Rather self-evident.
4. Highly confused Guards
The real problem is that every guard is programmed to have all the same dialogs, be they positive or negative. They can swear eternal alliegence to you in one second and threaten to cut off your hand and throw you in jail in the next. Not to mention that while knowing you are both thane and the dragonborn they will still say "Wait, I know you ..." when accusing you of a crime.
5. Dialog options that portray my character as an idiot
In order to get and/or complete certain missions you got to use the dialog options, and often these are written in a way that either blatantly does not fit my character or worse, make him/her sound like an utter moron. The various questlines/quests also often have dialog options which just does not fit with those in other quests/questlines making my character seem like completely different people.


