At 6'2, a Buell Blast would be too cramped for you. A Kawi EX 500 would seem to fit your needs perfectly as well as the GS500. The Sporty also makes a fine commuter....windshields,bags ,etc are readily available .
I agree with the EX500 suggestion. However, when you get it, buy some decent flat black and paint the whole thing. That bike came in some ugly paintjobs. I just saw one over the weekend that had been completely blacked out and it actually looked really cool.
If you strictly want a fun, economical bike, get the 250 Ninja. I still have one, and think it's a hoot. Ultra cheap to buy and own. Very light and easy to use. If you want performance, it'll get old, but for practical, it's great fun.
Buying used: Yes the SV is a great daily bike. Also look for these: BMW F650, Buell M2 Cyclone, Honda CB750 Nighthawk, Honda Helix 250 scooter, Kawasaki EX500 Ninja, Suzuki GSX750 Katana or GSF1200 Bandit, Triumph Bonni or Thunderbird (99-01 sport is the the T-bird's best). ANY of these can be had for between $1800-$3500 if you purchase bikes that are at least 5 years old. Parts are everywhere.
I've got to go with a Hayabusa with Yoshimura pipes and a power commander, you'll look and sound great sitting in stop and go rush hour traffic and you'll never have an excuse for being late again.
If that doesn't work for you, then I recommend a twin like an SV650 (generic and souless), Buell CityX (you'll look like a circus bear on a bicycle tho') or finally my personal fav, a Monster S2R Dark now with improved 12000 mile service interval.
The XB Lightning, either the 9 or the 12. You can pick up a couple year old one in you price range, or an old stock NEW unit for a little bit more.
Go to a H-D dealership and sit on one. Ride one if they'll let ya, and see what you think. Most people fall in love with the ergos. I have been commuting on one for almost a year (the 1200) and beating the crap out of it. I'm getting MPG in the low 40's, and other than tires, gas, and oil, there is very little you need to do to these things.
And OMFingG the little beastie is fun to ride....just be prepared or attention, controversy, and to take a little crap from people about the "bear on a bicycle" thing. (I'm about 5-11 and around 250).
If it is comfortable for you to ride, consider it. Also go back thru the archives and read every shootout in which the Lightning represented. It won every. Single. Time.
I think the Honda 750 NIghthawk (1991-) is hard to beat. I picked one up a few years ago with 12k miles in pristine conditions and with lots of extras for about $2300. I put on about 10-12k miles every year for four years and the maintenance was almost nothing (self-adjusting valves!). I keep good records and I could tell you exactly how much I spent, but nothing ever broke on that one, except for a wire in a switch, which I re-soldered, and I changed the valve cover gasket once. The rest, normal maintenance. It's as reliable as anything and it has enough power,but not enough to scare you.
I would look on ebay or cycletrader.com for any leftover bikes. Recently they had brand new zero miles 2003 Kawasaki z1000's for around 4-5K. Great around town bikes with a good engine for what you are looking to do.
Don't sweat it. Your list is good, though I'd away from the 250's if you plan to hit the freeways at all. They're great around the city, but not much grunt for higher speeds. Personally, I'd go for an SV650 or DL650 over a GS500 for the simple fact they're modern, better built Suzuki's (the GS' I've seen rot and rust away pretty quickly). I ride a DL and several friends SVs and we love 'em -- though I keep dreaming of a DL750 or DL800.
If you can afford a Duc Monster go for it and enjoy the sound and torque. I've heard both praises and dissatisfaction with BMW's F650s, so check 'em out more before buying. Nuff said. Almost any modern 500-650 is decent these days, so pick what fits ya.
My knee-jerk reaction to your post is to suggest a DL650 V-Strom -- it is perfectly suited to your usage intent. However, they will be difficult to find for less than your $5000 price target.
I own a Monster, and they're great bikes for urban riding. They will be a little bit more expensive to maintain (unless you do the maintenance yourself), but they are pretty simple machines, look great, and are a lot of fun to ride.
Someone suggested a dual-sport like the KLR650 -- also a very good choice, especially since you're not spending a lot of time on the freeway. The Suzuki DR-Z400 would be a good alternative to the KLR, and may be less expensive on the used bike market.