I'd like to partially retract my earlier statement about Defeat X Units challenges (in my case, 30 units). Having just gotten one, I'm realizing the difficulties associated with it, and many of them are the same difficulties as with the other combat-oriented quests. Yes, I can theoretically hope to do it with a lot of luck, but as a non-combat player, it's highly unlikely, and it's not something I'm willing to spend my day doing.
I mean, think about it, there are plenty of players out there who have minimal to no standing army apart from a few units for city defence (most or all of which are probably unattached units). So, to defeat 30 units, they could well stand to lose their entire army and still not succeed, or they have to spend their day constructing military buildings in space that's probably already allocated to other things, spend more time recruiting units (by which point, the day is probably half over, or more), then go find things they can actually kill. In a quick perusal of my options today, that turned out to be a lot more difficult than I'd imagined, since most players who do get into combat have bonuses to their combat from various GBs and I don't. My Continent Map is mostly already taken by negotiating, or unscouted so I can save scouting for the event quests that require it, so little help there. Even if there were available combats, losses would outstrip my ability to create new units, or at the last, would mean I'd be spending my entire day doing it. I might manage something with GE, but honestly, I've stopped caring whether I actually could do this quest long ago. Combat is simply not something that interests me. So, at this point, any combat-related quest is an instant "won't/can't do" for that challenge.
I fully acknowledge that this is a play-style choice on my part, and I'm quite willing to the lumps that come with my choice. I just want to be sure that Inno realizes that there are a large swath of players out there just like me who simply won't find combat quests doable, or at least, not worth the effort. As long as there are periods where it's possible to go 7 days without any combat quests occurring, I'm fine with the limitations of the play-style I've chosen. If there are no such periods, this new "feature" will likely go largely ignored as undesirable.