Since we are all giving our 2 cents, I would like to give mine. Personally, I like more “traditional” sales. I like money off of what is already available, especially when it brings it into a nice price.
For example, The Guild Seals Elite pack for $5 when on sale. I love that. And it is one of the few times I still buy in this game. I bought it 2 weeks in a row and so did most of my Guildmates. What I wouldn’t buy would be something like: The Elite pack at $20, but this week only, we added extra keys. Its still $20 for a one time purchase and that deters me, hard, as it would many others, I assume.
So, the current way you do Guild Seals pack sale is what I would like to see for Gems. Instead of adding more gems in, take some money off of what is already offered and assuming it’s a reasonable sale (not a Wal-Mart sale where you take off 3 cents and call it a deal. Haha), I would happily buy it.
On a side note, I will say that I enjoy your subscription packs as well. During my first 10 months in game (i say that, because I bought less after the Gem nerf and new UI, which was when that happened, about 10 months in), I used to buy the sub packs all the time.
I bought the Daily gold one 3 or 4 times in my early days, because I was in a Top 25 guild and was also trying to build kingdoms. I bought Daily Gems a couple times. And I bought Path to Glory 1, a couple times. PtG 2 I never did though. I wanted too, especially early on, but $50 is hard to come up with for one transaction, sometimes. All in all though, I do like the subscription packs, as a whole, though.