Sure, Pioneer Square has a bad reputation, an undeserved one. It consists of beautifully preserved late 19th century structures that were clearly impacted by the dot.com dollars. I saw it ten years ago and today it is a completely different place. If you like history you will love this charming neighborhood. It reminds me of both Vancouver B.C. (Gastown) and Boston.
Unique Suggestions: Check out the Klondike Gold Rush National Historical Park. Clean, interesting, friendly staff, and FREE!! Lots of neat antique shops and a lively nightlife as well.
Cheesy but still fun: The Underground Tour.
This starts at a little cafe called 'Doc Maynard's' in Pioneer Square, downtown. It's touristy, but silly and fun.
The Seattle Underground Tour in Pioneer square is advertised as a hidden city under the city. Its actually just a bunch of basements...they are even occupied with storage materials. The tour guides lead you down an alley way where the homeless have obviously been urinated (the smell is autrocious) and their are rats everywhere. And might I add that they have the nerver to charge 7.50 per person???
Unique Suggestions: bring a gas mask and dress in a safe suit? Its not worth the money, you would be wasting a beautiful day underground in a smelly basement ..is that not enough?
Fun Alternatives: There are duck tours in downtown. Just as cheesy only to the nth degree! Tourists are driven around town in a musical bus in the shape of a duck..later this bus converts to a boat and tours you around the sound.. Its too cute and perfect for children!
Around Pioneer Square/Seattle Center/Pike Place market on occasion in summer(the tourist season) There are people trying to promote charities/sell watches(99% chance their stolen) on the street, you just have to look at the person, if they are supposed to represent a church, why do they look like they just got out of the county jail. :)
At Safeco field, there are people selling tickets the day of a game, more so if its soldout and against a popular team like NY Yankees. Technically this is illegal, but the real danger is being ripped off with fake tickets, so I would advise buying tickets from the box office, so your not out of luck.