I think I might as well give my view on these bugs as I commonly encounter them myself:
1. This seems to be a problem in the server or the connection between the two users (you and the person vanquishing you). Normally, the game detects you got vanquished and initiate the "killcam". At the same time, the opponent is supposed to receive data from you that you got defeated by them and play the "ding" sound with the appropriate on-screen information. It seems to be the problem with sending and receiving the data to confirm the vanquish thus leaving you there for a brief moment while the connection tries to stabilise.
2. This also seem to be a connection issue as the game needs to confirm you are properly connected to the server and game, get all the required data and such. Those with a better connection seem to join quicker apparently.
3. Yes, this is a lag issue. This occurs when your game detects you vanquish the opponent while your opponent vanquishes you. Both or one side can not receive or send the correct message to the other client/server quickly enough so it delays and just simply processes as "you just vanquished each other". This lag can cause some strange vanquish orders and award the incorrect XP bonuses such as "Vanquish from the grave".
4. The ability involves Kernel Corn throwing an item onto the ground to mark the vicinity on which corn bombs would fall. This problem is that the bombs can fall on any solid surface and stop there. As you said, it is likely the projectiles are stopped by some sort of solid surface. However, it could be another lag issue as it is possible the initial item (like the potato) and the corn missiles could function as two separate "attacks" thus resulting to a delay.
5. Infinity Time has so many bugs, it is more unstable than Destabilized Time. The game is long so a bad connection is not recommended and the game has many factors that may cause the game to panic and give you a disconnect. Sorry but I can not really point this out as I receive too many bugs such as incorrect drops and freezing Gnomes. I made a list of bugs in Infinity in my "Lost Rose piece thread" if you are interested.
6. This is the opponent not receiving the information that they are stunned by you. Yet another lag problem similar to most up here.
7. This is the loading screen "loading quickly". The loading screen does not display until you are connected enough to confirm you are in the game. Between this time and the loading screen appears, the game loads the required assets (map, objects, etc) and therefore does not require the loading screen to display as you already got the things loaded.
8. This may seem to be a problem with the whole idea of "my entire fragile and important save file is saved on a stupid server" idea which makes me loathe cloud storage.
9. Yet again, this is a lag problem with the whole "interaction between players" idea. Person one heals person two but person two receives the information later so the sound plays later on person two's game as well as receive the progress of person one's revival.
10. I would definitely love small details like this. As a Rose player, I need to know if it is beneficial to use my abilities in advance when visuals are blocked by factors such as Stink Clouds or lag. Get to it PopCap!
In a nutshell, most of the problems seem to be lag. It may not rather be you but the server. I can not really tell as I do not know how optimised your connection is but I certainly know EA's servers keep messing up.
