Here's my Opera Mini wishlist (S60 platform) and comments:
1. IDNA whitelist doesn't contain fi tld-domain, oh why?
2. Some times left marging is completely missing and it requires screen to me scrolled to left constantly to see left most letters. If I stop scrolling to left, half or full first letter of each row is outside screen. It's also very annoying. Mostly this feature occures with mobile Wikipedia.
3. Opera often returns empty pages. Hitting reload several times fixes the problem. But why it's required.
4. If screen orientation has been switched, Opera doesn't recognize touch screen clicks correctly. This is old, but very annoying when you have device which turns screen orientation when using keyboard. One way to deal with this, is opening keyboard and using landscape mode all the time. Which naturally isn't what I want to do.
5. Some times links or page requests and responces are mixed between tabs. That's actually pretty strange. But all pages still are pages that I have visited or have links on pages I have visited, so at least it's not mixing data between users as far as I know. Some times system gets really messed up, when using 10+ tabs and Opera Mini for longer time. After that wrong pages are returned almost every time. Only way to fix that nasty situation is to restart Opera.
6. Opera should have internal PDF reader. It also also should be able to re-wrap text to make it well readable on phone screen. Technically it could preprocess PDF files on server and transfer and present those using Opera Mini's standard transport and UI. It would result as best possible UX. Therefore PDF files should not be any different from any other web-content. Now downloading files and opening those using slow native application isn't user friendly at all.
7. Option to clear privacy information on application exit.
8. IPv6 support (very low priority) - http://www.worldipv6launch.org/
9. Positive feedback: It was really nice to be able to disable that annyoing automatic phone number detection.
I'll be posing more stuff soon. I have just been really really busy with new technologies, testing, studying, etc.