Messages

 1. An offline client, allowing you to play campaigns against bots
Definitely a function I would use - especially when the internet connection isn't great.
2. A bot with a setting for different play styles
Would help keep it interesting.
3. A strong bot.
Definitely.
4. Options for timed games
Yes please.
5. Options for undo settings
Only when the undo doesn't allow for an advantage such as seeing the next card.
6. Online mini-tournaments; the option to easily create one for you & your friends.
I don't have any views on this one.
7. Option to invite specific players to your table
Yes.
8. More translations (to what language?)
N/A
9. Better animations when cards are gained/bought/played/...
I think the current play works well.
10. Better visualization of split piles, Archive/Crypt contents, Prince targets, ...
Same again.
10. Option to hide the log
Yes, I think this would be nice.
11. Android app (or just improved compatibility?)
Yes.
12. iPhone app (or just improved compatibility?)
N/A
13. Downloadable game logs
Not something I'd use.
14. Improved moderation (dealing with chat abuse, slowplayers, ...)
I haven't used this before.
15. Tutorial on how to play Dominion
N/A
16. Tutorial on how to play dominion online.
N/A