It's been a while since I sat on a Wee, but IIRC, the ergos are pretty similar. From the seat, the Wee looks to have a longer reach to the bars, but that may simply be a visual artifact of bulbous front end. The Tiger looks much slimmer from the seat. Cost wise, the Wee has it all over on the Tigger, especially since you can get a used Wee. The suspension, brakes, and engine on the Tigger are better, although the "betterness" of the engine is more a matter of opinion at this stage. Yeah, it makes more power, has more torque, and is smoother, but one thing it doesn't have yet is the history of reliability that Suzuki's 650 L-Twin has behind it. The suspension being better doesn't really matter if you plan on upgrading it. Going from memory, the handling of the Tigger is a bit more responsive. Unfortunately, my memories of my testride on the Wee aren't great for comparing, because I had just come off an Electra-Glide I was riding for a friend, so the Wee felt really top heavy. Had I come off the STeed, likely be a different impression.
For a cost conscious commuter and utility bike, the Wee is hard to beat, although it has been beaten with an ugly stick, at least that's the way it seems when I'm looking at it from the seat. It's pretty weird, off the bike from almost any angle it's a good looking bike. From the seat, blech. To my eyes, the Tigger looks good from any angle, including the seat. Just wish they had honest dual clocks on it, not one of them annoying digital doohickeys.
The Wee is a good bike, no doubt about it, with a strong farkle market and enthusiast community. Having ridden both, and owned both a Triumph Sprint RS (955 triple) and an SV650, my heart goes to the triple. Your mileage may vary.