Totally agree with almost all your points.
Battle times should be spread evenly throughout the day. Guilds with members not in PST are severely disadvantaged by the current timetable. Next week, for example, when my country goes out of daylight saving, there will not be a single battle during my available game time. This will suck for my guild, and I'll probably be booted because of it. Yet I am available for 9 hrs a day! Could I suggest 6 battles, every 4 hrs? Or 4 battles, every 6 hrs?
The sacrifice 1.5x bonus should be the norm - with it, sacrificing is very time expensive, but worth it in the long run. The bonus should be something more, so it's actually a bonus. All it currently does is trade off time playing for silver pieces.
Quest cards - definitely should get better cards for questing higher levels. It's pointless questing level 7, when the cards are worth the same as level 1. This makes Level 1 cards cost about 8 Stam each, Level 7 cards 44 Stam each - FOR THE SAME CARD! I know where I quest.
How many hundreds of dollars must a person spend to get decent cards? I keep seeing the same names get MR and MR after SR, yet in 4 11x conjures, I've landed a total of 4 HR and 1 SR. No MRs in sight. If this is indicative of the results, then people must be spending hundreds of dollars a day on this - so much for a 'free' game.
Which brings me to a point that wasn't raised, but was raised in-app, viz. how to make the game fairer for new players. Currently, you are trying to address the problem by gifting them an SR. Like that's gonna work. What you need to do is let them know that to be competitive, they have to spend a couple of thousand dollars buying high cards. Then spend the time in game to level them up. Then, just then, they might be competitive.
The matching, well, what can I say? There really should be a limit on how different the two teams can be. Teams outside top 100 should not be facing off against top 5 teams. It's not fair for either team. Why not set a limit of +/- 25 places? And you can't battle the same side twice in one day.
Guild ranks - I concur with the opinion above. But, GO and GM have the most important jobs, looking after the guild, but get pretty bad advantages, esp. when compared to some of the better ranks. It's nice that there's some choice, but really, people want to get the most out of the game. Some kind of rank that increases as you do would be a far better option. For example, MP restoration might go up when you do a certain amount of combo increases in battle. EXP rate for sacrifice would go up after a certain amount of sacrificing, etc. This would encourage new players to progress, rather than just sit there getting frustrated because they're going nowhere.
Further on guild ranks, how do players know when new ranks will be added? It seems very arbitrary atm.
Bump number of card slots. Ridiculous when there are so many cards available to have a maximum of 100 spots.
The other thing, which I still can't get my head around, is why a low stat C card has the same benefits as a high(er) stat C card. If I sacrifice a Cthulhu for example, I would expect that it would have more effect than sacrificing a Kobold, because its stats are a lot more. If you're going to give same level cards widely different stats, you should follow through with it. My solution would be to give all C cards the same stat total, just being different in the allocations to ATK/DEF, if you wanted to make a difference.
Why are some R cards rarer than others? There was a time when I conjured 5 Starlight Princesses in a row (not counting the Cs and UCs), yet there are many Rs that I have never seen. Other common ones are Vine and Gemini, yet they have the same 'rarity' as the other R cards. This does not make any sense at all.
Anyhow, that's enough for now. Not even going into the inadequacy of the event rewards, or changing the cards midway through (adding skills to previously unskilled cards
) or letting people put Cs up for trade wanting MRs in return, the lag, letting people attack after battle has ended, ...