League-of-legends – way to display (enethe) champion basic information while in a match

You can type /w username message to message an online friend. If your friend replies to the initial message, you can just type /r message/. If you want to send another message without a response, you have to use the /w method again.

The /r method will automatically fill in the username of the friend you are having the conversation with when you start typing the message. (It fills it in with the last user that messaged you)

/w = whisper

/r = reply

They have to be on your friend list as well as in the same region as you for this to work.

If you have a friend that thinks it is fun to spam you during a match, you can use /mute username, which will stop chat for your game's duration. I would not recommend using /ignore username as it will remove your friend from your friend list.

[..] a bigger Champion means a bigger target to aim for by enemy skillshots.

This is correct, but isn't necessarily a disadvantage. Most of the characters with large+ hitboxes have more hp, armor, magic resist, etc and are better suited for taking damage. With a larger hitbox, it's easier to intercept skillshots and other abilities to protect squishier allies.

Also, characters with large hitboxes can stand on "top" of other champions, making them harder to target.

Other than this, I can't think of any direct advantage provided by a larger hitbox. Spells that increase the hitbox often directly affect the champions stats (think of how Cho'Gath gains HP with each feast), but the size increase itself does nothing.