I don't think it should be easily achievable. That would take out the fun of it. I have 82 topics, so already I have beaten both of Slasher's suggestions.
I think 25/50/100 is alright. Maybe another award for the frequency and quality of topics, not only the quantity.
You'd only be at tier 2 for either suggestion, so that's not really beating them both. Furthermore, just because you make a bunch of news topics for every game that comes out/soon to be released, doesn't mean that everyone else does. After all, you've already been making all the threads for that, so it's not like anyone else can make copy threads. If we took away all your video game news threads, you'd probably only have about roughly 20 non-news threads. I'm not saying to stop or anything, I'm just stating a fact.
So all that has to be taken into account. My numbers couldn't be any more reasonable if I tried. It leaves a lot to be achieved for a forum of this size. Even though the awards shouldn't be easily achieved, they shouldn't be impossibly high either.
Also, "quality" of threads can be subjective. To determine true quality would have to be based off opinion. That would be like only awarding the mafia badge to players who play the better than others. Not to mention the time and effort that would have to go into looking through each topic and judging it's quality.
As for "frequency", not everybody makes a topic constantly. That pretty much speaks for itself, considering most of our members haven't even broken 20 topics yet. And those that have been here for years haven't even broken 40. You, Rhyme, Mage and a few ex-staff are the only exceptions, as explained previously.