Gold packs seriously suck! They need to either be cheaper (around 130) or increase the chance of containing an ultra rare.
As it stands now,it's really pointless to get them,at least in rounds 1-5.Maybe later,when you have all the commons and uncommons you need,they become usefull,but still you can just buy bronze or pillar packs and increase your electrum ( bronze buys for 30 and sells for 39-41 ). Let alone the fact that buying more cheaper packs, like bronze instead of few expensive ones, gives you biggest chance to get a hidden rare (assuming of course that all types of packs have the same chance to contain a hidden rare).
If the price stays the same,I suggest decreasing the sell value of ultra rares to 50 and make gold packs contain 1 ultra rare.