Also in regards to the Pilgrimage, I'm fairly certain it's the late teens that they go out into the galaxy, I'll skim the timeline see when Tali was born and try to work it from there.

According to Tali's wiki, she was born 2161, and began her Pilgrimage aboard the Honorata, and it seems to be in 2183 from what I gather, so late teens/early twenties seems to be the age they go. Might be different for Tali being female and an Admiral's daughter. Both Rael and that other Admiral (mind-blank) said they got sent earlier than usual, and 16 seems to be a sound age for someone to think his ship can beat off a dreadnought...... tell me you haven't tried on a space game, using a tiny ship to kill and big bastard lol.