The screen resolution is a non-issue at
tablet viewing distances, and I very much doubt the new one can't handle your 128 GB card (maximum memory card capacity is a very frequently erroneous spec sheet listing).
Their most famous and aggressive innovation came with the introduction of the Retina display in 2010 for the iPhone 4, where Apple doubled the pixel resolution and Pixels Per Inch (ppi) up to where the screen appeared perfectly sharp for normal 20/20 vision at typical
tablet viewing distances of 10.5 inches or more.
Not exact matches
Both are higher than can be resolved with normal 20/20 vision at the typical
viewing distances for
tablets, so the displays appear perfectly sharp.
Since the
viewing distance for 7 inch
Tablets is around 12 inches their displays are not quite «Retina Displays» but they are still very sharp and close to the visual resolution limit for most people (who also don't have 20/20 Vision).
The iPad Air actually has the lowest pixel resolution and PPI of these Flagship
Tablets, but that is perfectly fine for all normal applications and normal
viewing because Apple's Retina Displays have PPIs high enough so that the pixels are not resolved with 20/20 Vision at normal
viewing distances.