The city commission shall appoint a city manager, who shall be the administrative head of the municipal government under the direction and supervision of the city commission, and who shall hold office at the pleasure of the city commission, and he shall have power and shall be required to:
(1) Appoint and, when necessary for the good of the service, remove all officers and employees of the city except as otherwise provided by this Charter and except as he may authorize the head of a department or office to appoint and remove subordinates in such department or office;
(2) Prepare the budget annually and submit it to the commission and be responsible for its administration after adoption;
(3) Prepare and submit to the commission as of the end of the fiscal year a complete report on the finances and administrative activities of the city for the preceding year;
(4) Keep the commission advised of the financial condition and future needs of the city and make such recommendations as may seem to him desirable;
(5) Perform such other duties as may be prescribed by this Charter or required of him by the commission, not inconsistent with this Charter.