Low entry price for new customers.
Apple already has entry level products for desktop and several IOS form factors. They historically have tried to avoid to much overlap between product lines.
Increases market share and unit sales because of #1.
It's not increased market share if it is just cannibalizing Mac mini and iMac sales.
Lowers unit manufacturing costs.
what does? Such a flexible design may (or may not) incurr very high manufacturing costs depending on how they manufacture it. There will also be a significant tooling cost for such a compete departure from previous form factors.
Allows Apple to deploy budgets more dynamically because of #3.
not really. There will be a significant spooling up cost associated with a new form factor, plus there is packaging, shipping and inventory to take into account. If this were a real plan it would have the potential to tie down large amounts of capital in contingencies.
Allows end users to scale to purpose.
That is essentially the only benefit. However the buzz for "scalability" is either "the cloud" or harnessing GPU(S) for more horsepower. Most folks I know that are interested in scalable computing are building clusters with commodity server hardware (Supermicro is popular) and using their mac as the window into their render farms.
It's greener - costs less to run and allows Apple to advertise "green".
Multiple enclosures is actually a recipe for inefficiency. I'd need to something that proves that mutiple enclosures (each with their own voltage regulation and thermal control) can be more efficient than a single multi cpu chassis with several big fans, thermal management and unified power system.
Allows users better aesthetics (ergonomics) in the office or home.
I am not sure you understand the meaning of those words? They are not synonyms. If anything aesthetics are often contrary to ergonomics and vice versa. Apple has historically put aesthetics ahead of ergonomics. Their products look great. But the hard edges on the MBP, lack of height adjustment on displays/iMacs, non-adjustable keyboards...
Increases the portability/luggability factors.
I'm highly skeptical of this, but I suppose it is possible that a pile of discrete components could be portable. I think the goals of portability and modularity are somewhat contrary. It would be easy to connect modules by cabling, but if it is intended to be portable you'd probably want some kind of nesting/docking interface. That I think would be awful. Too much potential for dust/boogers/coffee to get in the data path.
Decreases heat in small rooms and offices.
I can't think of any aspect of modularity that means less heat.
With Apple brand loyalty and projected option-box prices it will increase total profit margins for Apple.
You are basically re-iterating points you have already made.
Insure a longer MacPro product-line longevity because #10.
I disagree, if they chose to take this path with the mac pro they could potentially lose customers in droves. Quite a few enterprise Mac users fight tooth and nail to use the "non-standard" Macintosh in what is a primarily PC world. An exotic modular Mac such as you describe would have even less chance in such an environ.
Probably reduce system noise.
Reduced shipping fees and increase logistical deployment.
hmmmm actually I think the opposite. You should see how much packaging goes into a blade server setup.
One whole box for the chassis. Then a dozen pizza boxes for the blades.