What Jobs-era Apple realized is that a simple, distinct product line actually easier to market to consumers than a complex full-line. Easier to understand, easier to buy, less paralysis of choice.
The one place the lack of clones is hurting them is in Enterprise. Apple doesn't really want to be in that market, but they could outsource server/workstations to someone like HP for sales to larger companies only.
This being said, had they actually taken on the Borg at their own game they would be a very different company than they are today, and not necessarily a better one.
Keeping the clones wouldn't have helped them do the things you are saying, it would have just hamstrung them further.
The Fujitsu relationship is a bit symbiotic, in that they also co-develop SPARC technology. IIRC, SPARC V is Fujitsu's kid, while Niagara is Sun's brainchild.
As for Ross, Sun hardware has always been low-volume/high-margin. I guess they were aiming to make more money out of post-sale services and software than hardware. Ross made hardware that had to run Sun software. In that scenario, clones didn't hurt that bad. Apple, OTOH, has always been a hardware company with a strong brand.
Good you reminded me of that - I have no Ross in my interesting computer collection.