I once had a fight where my ally took a squid, he died once and left in the first minute, after a further five minute Lueosi and Geo boarded the squid and the round finished 5-1 to us.
Had a match timer been in there I'd have not met my new Ryder friends!
Also if someone wants to rage quit, its better to let them quit than give them the ability to abuse their crew over voice chat or troll the ship by burning hydro or kero or crashing into terrain until they're able to leave...
Or they'd just alt+F4 out the game, show up as internet disconnect and their slot becomes unable to be filled for the duration of the timer...
Though I do like the thoughts behind your idea and the reasoning I personally imagine it'll hurt more than help.