If we aren't all firm on this as hosts, these actions will continue to plague all servers.

Regarding #1: Telling the host to start

This is a form of griefing/toxicity. Ban for this as such every time to maintain a healthy server. If we don't all do it consistently these players (kids) will never learn.
Give a warning before you issue the ban so they know WHY they are getting banned, and hopefully over time word will spread amongst the players that doing this is disrespectful to hosts.

Background for those of you reading this who do not consistently host: This is crazy annoying to the host. I ban for it with either one or sometimes no warnings. If the server is full and we've been sitting around waiting for the host, then sure. But if there's 5/10, 7/10, 9/10 players in the server, don't tell me to start. I will ban you.

Regarding #2: Cheating

Things to look for:

Player names with abnormal font or no text at all. This can be seen in the pre-game lobby and acted upon swiftly and without mercy at that time. Many times they will say "Oh I just copy/paste the name. I don't use hacks that alter the game at all." This is a lie no matter how much you want to believe them. Ban them before they ruin the following game and cost you all your ethical players.
Players leaving the lobby space ship and walking out into space. This is a hack, not a glitch. Drop the ban hammer.
Live players chatting with ghosts and chatting while still in the game (not in the discussion/voting menu.
Teaming. This is different than 2 or more players who know each other playing together, which CAN be done ethically. Teaming is one player protecting the other or voting together knowing that one is the imposter. If two people are playing together, they should not communicate outside the discussion/voting phases.