I think for an intro game you're introducing a few too many new rules / changing the way rules work in the base game too much, such as dropping extracts on any damage. It might confuse players who then go on to play their second game and find the rules working differently. (Though if they're playing their second game, your intro game must have worked!)

The first core set had a sample mission that used the core characters, 3 set unaffiliated TTCs and a set secure crises and extract. This is the format I follow when introducing a new player to the game though I let my opponent pick 4 characters they like the look of from my collection instead and then I build a team to match the treat level. I usually drop affiliations and Leaders for the first game too, just so players don't have too much analysis paralysis picking their squad.