I have just been through this process myself and may I suggest that you will have to compromise on your expectations.

If you are not prepared to 'do a split hunt' ie hunt in different locations, then plan around your most desired species and see what else is available from the outfitter's you contact.

The time you spend in Africa depends on how many species you want to hunt, how much money you have and again, what is available from the outfitter/Ph in the area you plan to hunt. The outfitter should give you a good idea of how much time is required. Also budget to collect that extra trophy that may 'pop up'. As a rough idea, I'd plan 7-14 days and expect to spend down time travelling as something always happens to delay you in Africa. Be specific with your expectations when communicating with your outfitter and stay flexible.

Good luck.