Great questions, and I confess that I can't give you the best answer here, but I'll try.
I'll start with foreign policy events. The Iraq withdrawal is slowly underway, but it is only in the initial phases because the surge needed to pacify Iraq took time to implement. The Iraqi Civil War in this timeline still is underway, and like OTL will worsen once American troops are out of the country. The war is still underway, and thus spending on Iraq is still high, but the lower amount of troops would certainly offset the cost to a degree. However, the national debt overall is slightly higher than OTL, because the amount of spending on the Medicare is up significantly. "Kiddycare" means that there are
74.1 million American children now receiving free healthcare on top of the existing OTL population of Medicare enrollees of 44 million. So basically a third of the country is now receiving free healthcare, which is going to increase social spending.
On the other hand, while spending is higher and the deficit bigger, working class families are having a slightly better go at things than in OTL. The average savings for an American family of four on health insurance would be around $1,500~$2,000 a year considering the average family plan at the time cost about $350 a month at the time according to Google. So if you halve the payment (assuming they have, say, two kids on the Medicare youth plan) to $175 a month.
But the ACA of ATL is basically the same as the OTL bill plus Kiddycare, so it isn't perfect. The individual mandate isn't popular, the online marketplaces are slow and convoluted, and there is increased Medicare fraud being discovered on a regular basis. It's more controversial than the OTL bill to the right, and many independent/centrist voters are more skeptical of it than they were the OTL ACA because of the greater expansion of the government bureaucracy.