Hmmm, power to weight ratio...that is a good question.
I have an 02 S that I replaced the carb, and added an M4 full system. The bike was totally transformed for that alone, and I have not really bothered to dial in the jetting. (it has been so cold lately, that it almost seems pointless as I am a fairweather rider for the most part).
The bike still has the stock gearing. With that said, the S would wheelie in 3rd gear seated with a heavy tug on the bars and a fistfull of throttle with clutch. After the pipe and carb, 3rd wheelies with a dab of the clutch, or no clutch if standing, and will wheelie 4th standing with healthy tug and full stick with clutch.
I also have a CRF450, and when riding the DRZ, I am not constantly wishing for more power. Of course, it could take more power, and there are lots of ways to get more (cams, base gasket for more compression, larger bore kits. etc) but I really like to ride the bike in dirt with the street wheels, and to be honest, you do NOT need more power in the dirt at ANY time.
Even on the street, the bike will wheelie at 50MPH plus, so if you need more it would seem that you are hungry for street bike power, and maybe should get a race replica. I was looking to get away from the high speed antics that the modern sportbike tends to excel at, and was looking to improve these same antics at more reasonable speeds. I am trying to hold 4th gear wheelies for example, without picking up speed on the back wheel...however I still have some work to do, and do not mind practicing.
For converting to SM, the XR650R, and DRZ400 were the only two on my list since I live in CA and did not want to hassle with the DMV.
I have heard that many folks here in CA have licensed the Husky 450 SM for the street, and if it was a gurantee I would probably go that route. Lighter, WAY more power (almost equal to a CRF450), better components. You name it. The big issue is it is not a guarantee, and I have had enough of dealing with CA DMV. I also had a "quasi" exotic bike in a CCM, and I loved that bike, but I could do without the "uniqueness" factor. -I prefer to ride than work and fiddle non-stop. -But this probably does not apply to the Husky since it looks so well thought out...possibly better than the Asian bikes.
Sorry for rambling, but to answer your question, I have not yet wished for more power in the bike.