You're definitely right. I really need to break it in more before making any major changes. My experience on 450s tells me that the shock spring is going to be stiff though.
It's hard to give a fair assesment of the new yz since I have only about an hour and a half on it, but I'll give it a try.
This bike seems to handle way better than the 09 crf, without any work. The one thing I really liked about the crf was it's ability to stick to an inside line. The yz seems even better there. But it can actually drift out wide if wanted. The crf wanted to just pivot/square up. I can't tell you how many times this put me on the ground... High speed stability on the crf was not good, this seems great so far with the new yz. Handling should get better as I get it dialed in for my weight and ability...
The motor on the yamaha
is way better. You may have heard that the crf was like a 350. This is definitely accurate. The yz450 does seem to sign off on top but it's nowhere near as bad as the stock crf. Low/Mid on the yz is perfect for me. I'm not sure about all of the off idle snap/bark complaints. I think those that are complaining about it should spend a day riding a 250 2t...
The yz IS heavier than the crf and imo does feel like it in places. Mostly in slower sections. At speed and in the air, this is a draw.
The front tire (742FA) suuuucks baaaaad. It almost put me on the ground several times. This tire just lets loose without warning. Anyone want a free tire? Only used for one ride...
The rear brake also seems really touchy. Seems like very little modulation. I would imagine that this will get better with time? Some of this is probably user error, and getting used to the ergos on a new bike.
Reliability - I don't know about the yamaha
yet, but the crf was terrible. On day 1/hour 1, my crank seal gave out allowing all of the engine oil to migrate to the tranny side. At hour 2 my auto-decompressor broke. I had 3 cams in my bike before 15 hours were on the meter. I had to fix a leaky water twice, the fuel filter once (inside the tank), and the (4 spring!) clutch twice. Oh, and fuel in the oil. Regularly I'd remove 100+ cc's more 'oil' than what I put in the engine side. I got rid of the bike before this resulted in any other reliability issues (think bottom end).