Any cartridge from 243 win up to 30-06 sprg will work for all that you mentioned. (I don't believe there is such a thing as overkill for yote, unless you want the pelt) If you want the pelt use heavy for caliber bullets and they should pass through with less exit damage. For bear use the heaviest bullet for 243 and the mid range for 30-06. If a bullet/cartridge combo is good for deer it will perform as well on bear. I would not hesitate to use my 243 on bear. Bullet placement and construction is more important than cartridge choice. All the choices listed so far will work well but the 30-06 will have the most available ammo and more firearms chambered in it. Every major manufacturer in the world has 30-06 as an option. Tough decision. Save more money and buy 2 rifles then you can have twice as much fun deciding.
