Just to clarify some of those points...
Excellent battery life - depends on the make and model of the unit. Some are better than others.
Instant boot - Eh.. Not so much. My Ainol Novo 7 takes abut 1 minute or so to cold boot. After all, it is running Android - which is a flavor of Linux. On the plus side, once booted, it can go to sleep and be woken up instantly.
Works faster outta the box - than what? Even though most tablets come with some complimentary games and apps, it's like any other computing device - it will require finding, downloading and installing other apps to bend the default tablet to your needs.
No keyboard - Should read "No PHYSICAL keyboard". All such devices do have an on screen keyboard.
Connections with other devices is iffy at best - Well.. That's one of those things that falls into the "that depends" catagory. It depends on how much effort you want to put into connecting them. Wifi usually works pretty well, but once connected it's generally a matter of getting them to talk to each other.
Small storage space - Well... that kinda flys into the face of one of your Pros - Cloud Connectivity - and how much storage you've got there. But most tablets have an SD chip slot you can use to add more storage. The notable exception - the iOS line of devices. DOH!
Without internet connectivity your experience will probably be pretty poor - That would depend largely on the app in question. I managed to survive without internet access with my tablet for about 4 months (at home) as I had problems with my wifi router. Still, the apps I used worked fine - even the ad supported ones - without the cloud...
There's one more you can add to the cons list...
Flash - Much of the internet runs on Flash. Games such as Farmville on Facebook, most videos on YouTube, and other popular items - live and breathe Flash. Some content is available, but much of it is not. I know I've gone out to find a song on YouTube by way of the tablet - so I can turn a friend onto a band I've come across - only to be blocked because that video is Flash only. DOH! Sometimes you get lucky while others - not so much.