I think the FitBit force is something I'd consider as well if you are considering the Up. On the other hand, I think more devices/updated devices will be coming soon.
As a fitness tracker with limited battery, the apple watch may not be ideal. Fitness trackers may also provide feedback on sleep which I know I've found useful in the past but it also involves wearing the device 24/7. Also, depending on the battery, you would have to charge the apple watch during the day. This may not be a problem if you have periods of time where you will be sitting but if you have an active job or on vacation or other things, it may be more difficult to keep track of your activity.
I looked at the 2 others listed above. The atlas looks ridiculous, no way I'd wear that. The moov looks decent though.
I also considered the FitBit force. But a while back I read a review on the Verge and the up24 came out better. Also... I think it looks better. If it's something I'm gonna wear, that does count for me.
As far as Apple's Watch goes, I agree with your points. My main reasons for not getting it are:
1: I think its way too bulky. It's simply not elegant I think. Apple is obsessed with creating thin laptops, mac's, phones and tablets, yet with the one device where thinness really counts, they blew it (thats my personal opinion).
2: Battery life will be bad in this first version. I really believe that. There's a reason they didn't mention it at all in the keynote. I could have been a unique selling point... but they didnt say anything... which in turn... says a lot.
3: I need to have my phone with me. This is a deal breaker for me. When I go out jogging I don't want to have my phone with me. It's not even a point of discussion for me.
4: Its clearly a first version, even Ive said that in the little video. They never do that...
It's a tryout. I have a feeling a much better watch with all the bugs worked out, better battery life and a thinner body are a year or less away. This space is moving way too fast for them not to get on a yearly (of more often) release schedule. And I for one, can wait for something of quality.