Looking at your manifest more carefully, I am struck by the fact that you are VERY low on consumables. Like, ONE medi-gel 
To make Gold a little easier, you need to use well-built level 20 characters with decent weapons and good consumables. I'd suspect that you've been putting all your credits into unlocking gear and weapons and neglecting consumables. So I'd strongly suggest playing some more Silver and spending all the credits on a few JEPs so that you can go into Gold with at least level II stuff like Cyclonics, ammo, and weapon amps.
^ Buying one Jumbo Pack for 33k gives you 5 each of Missiles, Gel, Ops Packs, and Clip Packs. That's 20 consumables for 33k, or 1,650 credits per consumable.
Buying one Spectre Pack for 60k gives you 5 of one random type of consumable. That's 5 consumables for 60k, or 12,000 credits per consumable.
Buying one Premium Spectre Pack for 99k gives you 5 of one random type of consumable. That's 5 consumables for 99k, or 19,800 credits per consumable.
Stop buying Spectre and Premium Spectre Packs until you get more consumables; preferably max them out so they come off the drop table altogether. Then you will get more Rail Amps instead, but that's a whole other set of price analysii.