Ugh, I agree, I think we do need a little sound effect or something to notify us that we earned an achievement/medal.
I hope this medal feature returns because I love completing things. I just hope that we don't have any crazy medals like [mocking voice]"play a funfest mission with 30 people[/mocking voice] or [mocking voice]pass by 1000 people[/mocking voice]. Because seriously, these were ridiculous. Why won't 5 people playing a funfest mission be enough? And why not pass by 100 people instead of 1000?... I will never get all the medals because of these two and I really don't have that thing for collecting that many medals in this game when I know I can't win them all.
I say, yes, bring the medal system back, but don't give us any ridiculously annoying medals that we have to rely on others to win them. At least they could let us make the funfest missions online.