I experienced issue #2 as well on power39. I had VDD1 & VDD2 set to 1 in my /etc/pmconfig. With the stock kernel I was able to boot and run with better battery performance with those settings.

After upgrading kernel to power42 I disabled vdd2 in /etc/pmconfig but enabled it in the kernel config file I set as default (using stock voltage settings , overclocked to 750Mhz, my N900 without smartfeflex was never stable above 750). In my opinion I have experienced stable performance with good battery life based on my daily use (email checked every 30 minutes, music during commute 40 minutes each way, intermittent calls etc).Don't ask me to quantify with numbers.