Thanks for the very detailed and thorough response terra! I'll try to tackle all your points as best as I can:
1. True, however more players playing means more money for SC. On the player's side of it, more players means more potential for inactive bases (sure lots of active ones), as well as extra resources gained from the Quests themselves.
2. As a business, all SC wants is for you to play (and hopefully spend) so they WANT ways for you to spend money and reasons to play (especially with Holiday spending). They don't want to have you not play the game, they want us in as often as possible, holiday or not. As individuals, I totally agree with #2, but as a business from SC's perspective, that is the opposite of what they want.
3. If you look at the Quests, many of them will not cost you a lot. My suggestions are just examples by the way, SC could add even more resources for completing them. But you would definitely turn a profit by completing Quests, not to mention the Wheel rewards.
4. That's totally fine, Quests are optional so if they don't want to get attacked to complete a defensive Quest, they don't have to. For people that want to get Quest Jewels and resources, they can do them if they want. That's the beauty of the idea, you can do them if you want, and not be penalized if you decide not to do some or any Quest! As far as your point about people having really tough bases and never getting attacked, maybe that could be part of the Quest (like get attacked and win a defense, or without having a shield, don't get attacked). There are solutions for every potnetial problem hehe. For your last point about people at high trophy count not bothering to get this Quest done, that just isn't true as they literally wouldn't have to do anything different to hope this Quest gets done haha. I was a recent Champion so I know ;)
5. Those specific rewards are controversial and I totally get why. It was just an idea, so a better idea may be a week long boost to resource production. I don't think it would be overpowered though to add extra mines. To your point though, I actually think the OPPOSITE haha! I think due to how little of walls we have, it would HELP get 50% easier as these extra items would be placed outside walls most likely and be easier to destroy.
6. Yeah, the ideas I made, like I state in the thread, are just ideas and SC could add whatever rewards they wanted. here's my explanation though: the rewards need to be extremely good. They cannot be overpowered but they need to be worth the effort of spending a month trying to complete Quests. In addition to that, there need to be rewards for people who have maxxed bases and have no need for resources. Besides decorations, the only other thing would be boosts to help them in battle/wars/pushing. The boosts would be minor, and maybe extra time or extra troop slots could be bad especially with wars, but I like the idea of added chaos/unknown/mystery throw into the predictability of the game. The rewards would need to be balanced, but now you can see where I'm coming from.
Really good suggestions though! I like the idea of a time limit but maybe make it longer, and give the ability for when to start one. I don't think they should be so easy that every single Quest can be done by everyone no matter how casual you play. Some should be easy, some should be hard. If they are all easy, the idea would be a huge waste of potential IMO, and not nearly as fun or rewarding.
Also good suggestion about the extra level to mines, I should have added that to the OP (and I talk about it earlier in one of the comments) but if I remake this idea to update it, that's what I'll include.
Thanks for spending the time to write back, let me know if anything I've answered is confusing or wrong in your opinion :)

