One reason why I don't play on gold with randoms is because they will be assholes quite often, wrong class? kick, not standing in the right place at the right time? get insulted and called names.
Luckily, my last few games have had a lot of lower level, but extremely helpful random teammates. Got paid on Gold/Cerberus/Glacier with a semi-ideal team. I've never voluntarily wandered into that map with a prearranged team. It was much easier than expected.
If I don't see an Infiltrator I will switch to one. Other than that I'm not going to bother with ideal setups. I have seen too many successful soldiers, krogans and vanguards to be worried about it anymore. The only time I am worried about an ideal team is if I want a sub-20m clear. Otherwise sub-30 is no big deal.
When the Resurgence consumables finally arrive I will be using a lot of Batarian Soldier on Gold. Sabre II AP/Damage - CarnifeX Stunner/Barrel. I want some melee III amps to complete the package. Willing to bet I'll still take top score on an average team.
That's the way to do it on Firebase White. On wave 11 stay down below in that room until 30 seconds left then run like crazy to the extraction.
There is an easier way. Get everyone to the small room near the stairs. Every enemy will spawn below you. For bonus experience (thank you 3 1700+ N7 players) it's very simple to net 3 killstreaks with 3 cobras. Just count to 5 and release. Since all enemies spawned below you the landing zone run will be unimpeded.
I hardly use consumables unless it's absolutely necessary. Like, I'll often rather die than use a medigel, either because the wave is manageable for the rest my team or they are so bad that it's hopeless and a waste of resources.
I used to be that way, but I've solo saved a wave too many times to worry about stockpiling medigel. That said I could really use some equipment packs.
I hope next week's special is a Spectre Support Pack. 10 of each consumable, +5 more of 2 and a few level III amps.