Kar artifact and bundle is not the same.
A Kar artifact should be seen as a features:descriptor.
When you drop a features descriptor into the deploy folder, or register a features descriptor using features:addurl command, no feature is started automatically. You have to start feature by hand.
It could make sense to be able to define a set of auto-start features in the etc/org.apache.karaf.features.cfg file.
For instance, we could have a property like:
features.auto.start = myfeature1, myfeature2, myfeature3/version
When a features descriptor is registered (using features:addurl), Karaf could check if the features descriptor contain features defined in features.auto.start, and try to start it automatically.
Another way, could be to add autostart attribute in the features descriptor:
<feature name="myfeature" version="1.0" autostart="true"/>
Let discuss of that on the mailing list.