I'm having issues with the caravan tents loading. I Googled the issue and found it in a list of bugs. I also noticed that this glitch didn't start occurring until after I completed the quest "In My Time of Need". The other glitch where the two guys who initiate this quest stand around the main Whiterun gate forever happened at the same time. I don't know if the two are linked. I know I can still trade with the caravan, but at the same time it's annoying to me and am wondering if this is being looked into. The page I read says this glitch (invisible tents) can sometimes fix itself... But I don't want to be forty hours into a game and then realize that it probably isn't going to revert to how it should be.

I assumed the tents not going up was the result of the Khajiits and my character entering the cell at the same time (they're walking, not already in place). When I enter/leave the cell, the tents are there. I even watched, once, just to see if there was an animation of the tents going up, but one does not exist. I'm guessing this is due to the lack of said animation, and thus player must leave/return to see them in place.

As for the Alik'r warriors, get used to them. They'll remain there until the end of the game, and it's due to the completion of the quest.

The two glitches don't seem to be related, but this is Skyrim. Opening a door in Solitude will kill someone in Riften.

Just remember, there is no quest glitch in the game that can't be resolved by loading an earlier save and doing the quest again. Fortunately you rarely have to do that.

As for the few world glitches that are out there, they don't impact the game, and most of those go away the next time the cell loads.