All those are intentional downsides. They are what gives the summons character. Make them more than just fighting machines. Why do you want to remove them?
It should equip the spear for you, then run over and give it to the skeleton. I checked that it works in the latest version. Probably a mod compatability issue.
Specs are the same. Which weapon are you giving it? Some weapons are limited, such as nightmare sword because the skeleton doesn't have sanity to use it.