The best value combo for resist crystals

The new chest exchanges are a bit complicated. I already wrote an analysis of the pumpkin carriage, and another about glass slippers. Today I would like to show you what's the most efficient combination IF you want to spend some balens to get the maximum number of resist crystals from the current resist synthesis event in Wartune.

The current resist synthesis event came a bit too early. Usually I can stock up enough free resist shards from maps, could adventures, dimension chests, etc. so I can make one or two lvl 7 resist crystal, and one of everything else on all 4 days. (Yes, 4 days, since on the first day, you can make one combine between 1am and 5am, and one after 5am). But now I was a bit low so I looked around for possibilities.

7 glass slippers can be exchanged for 1000 crystal shards. After I have the persian cat, I think this is the best trade for glass slippers (but only because I have orange sylph already, so I don't need mahra that much). So far, the best balen buy for resist crystal shard were the gamble crystal chests, which contained 30, 40, ... 1000 crystal shard for 39 balen (not for sale last 2 times, sadly). For 1000 balens, I could get approx. 6500 crystal shards, so on average, one crystal shard cost me 0,15 balens. 

So, 7 glass slipper for 1000 crystal is a 21 balen / crystal slipper exchange.

Currently, they run a one-time bag promotion.You can spend 2000+ balens to get a lvl 5 resist crystal (which needs 8100 crystal shards, worth 1200 balens), some gems, and 15 chinese chests. It's a decend bonus. You can buy 57 chinese chests for 2223 balens, which is 2023 if you use a 200 balen coupon (I hope you still have a bunch in your mailbox from Christmas). The 72 Chinese chests will give you on average 24 pumpkins (worth 21 balens on average after you don't need the cloth), 24 glass slippers (worth also 21 balens if you exchange them for crystal shards) and 24 paper cuttings (worth about 25 balens each, if you exchange them for Vulcan packs, more on this later).

So for 2023 balens, you get 72 chests (worth 1608 balens), a lvl resist crystal (worth 1200 balens) and some gem packs, so it's an okay deal. Still, don't this push too far: you need only so much resist crystals so you can make ONE level 5-6 crystal each day (and a lvl 7 every 2nd day). So you should buy this pack 1-3 times max, no more.

About paper cuttings, I am still thinking whats the best deal with those. Unlike with pumpkins, here the items you get for opening the chests are crap, while some of the exchange items are very good. 

Empire truncheons: new item, and you need a lot. Still, I'm sure they will add an event which gives a constant source of these (titan wars), so I won't go for these unless I can get 400 right away.
Good luck charm, fashion core: these are the best value item balen-wise. If a clothing event will run while this exchange is still available, and I run out of these resources, then I will get them from here.
Vulcan Pack: This is pure +ATK, and very hard to get, so this is the most tempting for me.
Clothes: Clothes are always cool, but the above items are much better. And these are quality B anyway. I will rather get them a few months later when it's sold or given in a bundle.