People really need to stop looking at Apple's business decisions with blinders on and only for their specific use case. Apple makes these decisions based on how they want people to look at the product offerings and at what point they consider somebody that should be looking at a higher price machine.
More or less, i agree. A great deal of thought goes into the marketing of specific machines geared towards particular types of users. Apple made their choices expecting that most would be true to the Apple ecosystem and compromise by buying something more than they need.
Mini - You might want it to be fully upgradeable, but Apple looks at it as an entry level machine and the consolidation of the server option and other features/upgrades prove that. Apple doesn't like any machine to be fully upgradeable and they feel that you should move up to the iMac if you need Quad Core or more features. Sure, I'd love a Mac Pro in a Mini price-range, but welcome to the new age of computer purchasing.
Of course, part of the charm of the old Mini is that we can dig in there and customize it ourselves in order to customize it to our specific needs. It feeds the DIY part in all of us tinkerers. AND it saves us some $$ by not having to go thru the Apple Store and pay their high prices for customization.
Having said that, i can see why Apple took away the customization, they want you to pay them to do it. I disagree with this, but i understand that decision from a business perspective.
But, i think what the initial reaction of this forum points out is still true - there now exists a gap in the new Apple product offerings. Many of us want a quad-core machine for multitasking (i want one to be the center of a music studio that i can take on the road) and perhaps enhanced graphics capability BUT we want it to be headless (we either don't want to overpay for an Apple monitor, we have our own, or we just don't need one [for music performance, for example]). Six, eight or twelve cores are overkill for both our needs and our budgets (see: "artistic types"). I imagine the price point might start just below a grand and go to maybe $1300-1400 for the "dream machine".
Basically, we want an iMac-level or low-end MacPro powered machine without having to buy the monitor. We either don't want or need the 5K display. We want processing power and multitasking ability. In return, i think many of us (myself included) would be ok with the lack of user customization options, and would be willing to bite the bullet and pay Apple to do our customization for us. But, give us the computer (and the upgrade options) that we NEED/WANT!
Apple has left a gap here. I think one day they will fill it, but how far out in the future is "that day"? Undoubtedly in the meantime, some will work compromise with the new lower-priced Mini. Others will bite the bullet and go with the new iMac or maybe even a MacPro. However, others will leave the Apple ecosystem altogether, because the computer that they want is not a computer that Apple makes (anymore). And it's kind of a shame because they DID, and decided to STOP.
For myself, i recently bought/customized the upgraded 4-core Mini, but wanted a second one that i could take on the road. I'm kind of 'stuck' now, and i'll probably find a refurb Mini to do the job, since i've invested in the Apple ecosystem, Logic, etc.....
cheers!