ok, here's my gigantic crazy-person wishlist:
iOS 9:
FILE SYSTEM/ICLOUD DRIVE
-Revamped file system based on file extensions/metadata/tags rather than per-app or folder storage, using iCloud Drive
-file browser/manage in the space where Spotlight used to be (left of the home screen)
-Document Picker for attaching documents to emails, iMessages, etc.
-Versions support for documents
-ability to add songs found online to music library; same for videos
-downloads from Safari into file manager space
-totally redone system for homescreen icon arrangement
-links for sharing icloud drive items, collaborative or read-only sharing
-heavy use of tags feature emphasized over using nested folders
PHOTOS/PHOTO CLOUD
-face tagging/recognition in photo app
-improved animated gif support
-screenshots get their own separate album automatically
-images saved from Safari get a 'today' creation date instead of leaping way back in Camera Roll based on their metadata
SIRI/INSTANT INFO
-"daily report" for alarms with weather, appointments, messages, emails, reminders summary
-Spotlight/Siri integration
-text entry for Siri
-more Siri services
-offline Siri functionality where possible
-Google Now competitor (before-you-ask information stuff), using email and search analysis a la Google Inbox; handled locally where possible
-package tracking link recognition/support
-voice control API for apps, but Siri itself remains curated
MAPS
-offline maps support
-Transit directions again in major cities
MAIL/CONTACTS/CALENDARS/NOTES/REMINDERS
-smarter mailboxes with rules-based sorting
-address book groups
-Notes and Voice Memos combined into one app, retaining iCloud syncing for audio as well as text notes
-Reminder sharing support
-equivalent sorting/delay functionality to Google Inbox, Mailbox, the new Outlook, etc.
-"favorites/VIP" for iMessage, FaceTime, Mail, Phone - can integrate with e.g. FB Messenger as an API - used for fast communication and for do not disturb mode
-smart reminders and so on like Inbox/Outlook/Mailbox - pull flight info, package info, event info, et cetera from email messages
HOMESCREEN/NOTIFICATION CENTER/CONTROL CENTER/LOCKSCREEN
-lockscreen "complications" system analogous to the one found on Apple Watch
-deeper control center (press+hold wifi/bluetooth icons for more options), slightly more customizable for app launching, can be used to turn location services on/off
-clear all for Notification Center
-better homescreen icon sorting/moving process
-weather, stock, voice memo, calculator, passbook apps on iPad
-more dynamic icons (weather app icon auto-updates temperature/conditions, etc.)
-notification sharing between all apple devices (i.e. notifications on appletv for a phone call or FaceTime on iPhone/iPad; notifications on phone when a download finishes on computer)
-notification center should feel more like a useful to-do list, and/or like email: something you occasionally go through and clear out in productive ways, and it should be easier to customize it to get it to this point
-for the active app, control center can go straight to the Settings section where its privacy/notification controls are; also, ability to review it in app store, send bug reports
MUSIC/ITUNES/OTHER MEDIA
-Play Next support
-built-in Spotify competitor; built-in Netflix competitor
-TV app-channel solution along the lines of News Stand
-comic book mode in iBooks
-News Stand unfucked so it no longer obscures apps inside it
-Handoff support for music library, videos
-Apple iBooks Author adds simple authoring for News Stand, simple-but-excellent CMS stuff a la The Loop or The Magazine
-super-great native RSS reader (with socially-sourced content, RSS content, smart suggestions, curated sources, pull from reading list, pull from news stand apps, special subscriptions available e.g. to New York Times) for catching up on websites/news, fully-featured, well-curated, etc - also pulls in info from mail, perhaps
TELEPHONY/LOCAL NETWORKING/ETC
-FaceTime group chat
-stronger proximity-to-computer support (your own computer functions as an iBeacon)
-local phone-to-phone messaging, facetime, phone calls built in using Bonjour, daisy-chained Bonjour networks for emergencies (walkie talkie system)
APPLE PAY/PASSBOOK
-native "cash register" app to compete with Square
-Apple Pay direct transfers a la Square Cash to pay friends; Apple Pay support in all BT 4.0 hardware a la Square Register
-legally valid photo ID in Passbook, unlocked via TouchID
-built-in "key" support in Passbook for unlocking doors, mass transit turnstiles, security doors, etc. using TouchID and mimicking NFC/RFID
-scanning support for barcoded things like library cards, insurance cards, gym passes, etc.
OS SERVICES/MISC
-local transaction support using Bluetooth 4.0, NFC support
-print-to-PDF
-native VNC solution maybe
-easy access from within an app to Notification/Privacy Sheets for permissions management and App Store rating/review via control center or notification center
-Google login integration a la FB/Twitter
-shitloads of bug fixes; a "Snow Leopard" year
-unified Safari view for apps to much more easily add a browser, just like they can call up a Mail pane
-separate "app store" from "game store", make Game Center not suck
overall immediate hopes:
-music app revamp
-mail app revamp
-further apple pay upgrades, real-world identity/authentication
-passbook key support
-file browser, file picker
-transit directions
-lots of bugfixes
-anything whatsoever to make notes and voice memos and compass more useful and/or interesting
-redone homescreen icon arrangement system
iPad taking-advantage-of-screen-size hopes:
-improved homescreen (more icons, more informative)
-improved lockscreen (more informative)
-improved notification center (useful enough that its worth going to for more than just missed notifications - easily-digestible list of tasks along with the tools to digest them)
-improved app switcher (note/display which background services an app is using)
-improved control center (customizability for sure, *not* a dock replacement, but better app selections, ability to turn off location services)
-improved Today view (more like a full dashboard of what matters to you on a single page)
-great reader app
-multiple users/multiple settings modes
-more granular do-not-disturb mode
OS X:
-Siri, always listening via 'hey siri' and with a strong emphasis on accessibility features, and with the ability to run user Automator scripts (hell fucking yeah can you imagine)
-Control Center
-Mac can function as an iBeacon
-Mac can function as an AirPlay receiver
-separate Game Store and App Stores, game store still chart- and algorithm-driven perhaps
-OpenGL 4.5 support
-notifications on phone when download finishes on computer, etc
-smart handling of wifi versus cellular (so LTE can be built into Macs)
-Quicktime improvements (cropping and exporting), open up AVKit for third-party codecs
-Google integration a la Twitter/Facebook
-Use TouchID on phone to unlock Mac
-Handoff support for music library
-iTunes turned into Sync Services, plus universal App Store, Media Store, Music, and Video apps
-Music app is light dedicated music player with improved DJ/playlisting controls, full iTunes Radio, Handoff support
-Videos app replaces QT Player, given Handoff support where possible
-iBooks renamed to Books, given Handoff support
-App Store app contains Mac, iOS, and Apple Watch apps
-Media Store app for music, tv, film, book downloads
-Podcasts app separate from media app?
-Sync Services run in background and don't require any apps to be open for syncing
-merge PDF handling between iBooks and Preview
-shitloads of bug fixes; a "Snow Leopard" year; addition of UXKit
-photo library incorporated into open/save dialogs for apps that enable it (a Photos framework)
-likewise, apps can have "access to photo library" a la iOS (for more intensive apps like photoshop or lightroom)
-hella bugfixes
-kill the Dashboard ffs
-touchID authentication via Continuity
-tagging system added to notes, iCloud emails, reminders, voice memos, contacts
-big, thorough dark mode
-HealthKit, misc apps like weather and stocks
App Store:
-app bundles (OS X + iOS + Watch + TV)
-timed demos
-paid version upgrades
-app ratings and top charts deemphasized, reviews and curation given more prominence
-apps penalized for asking you to rate them