Weather syncs every 2 hours, I really doubt that pushing that out further is going to give you anymore significant battery life. I'm not sure about facebook.
I don't know if you've seen me post this before but you are really fighting a losing battle. if it's not showing up as being an issue on your battery usage then it simply isn't an issue.
What you should do is accept the fact that smart phones eat up a lot of battery and do it quickly. The way you're going shutting things down you will have no more then a regular phone.
Here's what I did. I went to Amazon.com, got a spare battery (8.00), got a charging cradle (MiKradle - charger not included) about 30.00, and I purchased a wall battery charger off ebay for 5.00.
When my Droid is not in use it sits in it's cradle, charging. When I have it away from the cradle I use it as much and as often as I please. The only thing I have turned off is bluetooth and GPS but if I need them, I turn them on. Yesterday I had to use my Droid as a GPS and I had it running for a good 45 minutes. I went down 10% in power. By end of day I was at 50% power and when I went to bed I was at 30% power.
I didn't have to but I did change batteries at that point and I was set for as long as I wanted to go for the evening. When I went to sleep, phone went back into the cradle and fully charged by morning.
Yes, it cost a little bit of money but for the peace of mind it gives you it's well worth it.