>>I buy an organic instant coffee from Amazon for just an euro or two more than the brands at my local store.
Agreed that the instant coffee on most US supermarket shelves is severely wanting (excepting a couple of Euro imports) but if there's a good one available via the big A you might mention the brand...?
That said, I really don't like anything other than ice in my iced coffee. I find the Aeropress perfect for that. I usually make about 400ml of iced coffee. 20g ground coffee, 100ish ml hot water into the 'press. If you're using a 'for filter coffee' grind, brew 3-5 minutes. Press into a tall (sized for 500ml) tumbler filled with ice cubes. Mostly the cubes don't survive, but there'll be bits of ice.
As a side note, for years I'd been making a mug of coffee using a regular sized aeropress (only size there was) to make 4-500ml coffee by making very strong coffee then adding hot water (sort of an Americano). Now that there's an XL aeropress, my regular sized one *only* gets used for iced coffee as the XL does a lot better job at larger volume. If you've been doing the same, go get an XL. It's absurd that a few pieces of plastic should cost as much as they do so I held off when the XL first came out, but the ability to brew larger quantities (400-450ml) inverted does IMO make for a better mug of coffee.