The prob is Archos already makes so many different products, they can't afford to make even more and so Archos has to choose to limit skews, limit the different capacities, and perhaps the work needed to add 1TB HDD version of Gen10 wasn't worth it for Archos, as adding 1TB in there adds thickness so it can hardly be called XS anymore, and the price to develop HDD skews is perhaps too high compared to just making more of the same skew 16GB with MicroSDXC.
For Archos to easily be able to release 5-6-7 different sizes and different skews per sizes, we need to wait and see if France's Francois Hollande or the EU does some strategic investing in Archos, for France and the EU to have a strategic leader in competition with US and Asian giants Apple, Microsoft, Samsung, Sony etc. Other than Archos, France and Europe has nothing else. With more cash, Archos can afford to manufacture many more of each skew, thus supplying all the worldwide demand for tablets, and expanding to more sizes like 5", 7", add 1TB skews to all sizes, and make more skews, some with SIM card slots to compete with smartphones, some with Pixel Qi screens to compete with e-readers, some with 11.6", 12.1" and 13,3" screens to compete with Ultrabooks and Netbooks, some as a laptop without touch screen to be a true ARM Powered Laptop, some with Chrome OS on ARM, Ubuntu on ARM, Google TV on ARM and perhaps even some skews with Windows RT.
Even robots and everything, if Archos gets more cash investments they can make everything at the same time.
I think the 5inch market is dying due to larger phones from 4.3 to 5.5 inches. Who wants "another device to carry arround" in a similar size (appart from me as my phone is small!). These days, bigger is better.
As Charbax said, it is down to money and market strategy. You have to sell to the masses, Archos were there first, but the market has changed. Cloud storage is the "new" thing, but internet coverage is the weak link.
Unfortunatly, minority groups are largely ignored. I run a photographic shop, but I don't stock black and white printing paper or chemicals. There is not enough demand for it and it has a limited shelf life.
I'm not saying they don't get it wrong. If google put micro Sd into the nexus 7 it would sell at least twice as many units, probably more (waiting to see what Asus do with their unit).
Everyone has different needs and uses. no device is perfect, we just have to learn to make do, or set up our own business and make it ourselves!