I'll second the spawn issues. Too many times you spawn, start to get your bearings, die. Spawn again.
The bolt actions do seem a little weak, but that's just balance with the other weapons. Some tweaks all around here I think. Hopefully this is something that will happen as the beta goes along till a good balance is found.
Dogs. Give me the heli from CoD 4 anyday. With the heli you can hide from it. Not so with the dogs. Rather than the current time limit I think it would be an improvement to just put out a set number of dogs. There is still the chance of getting multiple kills but it wouldn't be quite so dominating. One of the main things about the dogs is that they come from all angles so the distraction for the enemy is likely to allow you to get more kills anyway.
I'm not sure about the weapon choices regardless of nationality, but that's the same a CoD 4 so whilst it feels a bit more wrong in WaW its not exactly new. What would it take to have similar weapons available based on nationality and group the challenges together? Perhaps there is the possibility of a 'hard core' match type here where you are restricted to the correct nationalities weapons.
I like the tanks. They aren't hugely effective, but provide a distraction. With good team work the distraction of the tanks could provide for some interesting tactics.
There are other things but I think that they are based on a lack of familiarity with the maps rather than anything else.
One last thing War Mode FTW