Can I share different things with different buddies?

Yes. Buddies Settings starts with All Buddies: the settings every buddy follows. To change any of them for one buddy, tap Choose a buddy at the top of Buddies Settings (All Buddies / Choose a buddy) and pick them, or open their page and tap Sharing & Alerts. You can choose, just for them, your photo, pioneer status, streak, badges, pet, whether they see your plans and how precisely start times show, whether their plans show on your calendar, and Ask to Join Alerts and Badge Alerts on this device. A setting that's theirs alone has a highlighted layers icon and an undo arrow beside its name: tap the undo arrow to have them follow All Buddies again, or the undo arrow at the top to do that for all of their settings. Tap the layers icon to see their value and All Buddies', with a checkmark on the one in use. In All Buddies, a setting some buddies have their own value for has a layers icon that lists them; tap a buddy there to open their settings. Tap All Buddies at the top to go back. Undo in the top corner takes back your changes on that screen, newest first. Changing an All Buddies setting changes it for every buddy who follows it, but not for a buddy with their own. Pause sharing is for everyone: while it's on, no buddy sees your plans, streak, badges, or pet, whatever their own settings. Your name always goes to every buddy, and buddies aren't told about any of these choices. Sharing and calendar settings apply on all your devices with Buddies; alerts apply only to the device you set them on.