You will probably get arguments for both but I don't think you will see to much of a difference between BB and plane base especially at mid to lower velocities? BB base will load easier and you won't' have to flare your case as much. As far as leading you need to find the correct size bullet and hardness for your particular rifle. You may find it will eat anything without any problems at all. Gas checked bullets will also help with leading issues and can be pushed to faster velocities. Theses also another thread going about polymer coated bullets, if you can find them they also would eliminate any leading issues. Probably any trapdoor load at the higher end using a 350 or 405gn bullet would give you a nice plinker and take any deer sized animal in north america.
I'm sure you will get tons of other recommendations, probably will come down to picking a few variations and seeing what you rifle likes.
Good luck, T.