Put very simply... Photoshop for raster image manipulation, colour correction etc. Illustrator for vector drawing (logos etc) and simpler, one or two page designs (although I personally use InDesign for these). InDesign for layout. Acrobat Pro for checking and fixing files for print if necessary, and in many cases, imposition via a plugin.
Pro does let you do some work on a PDF if it is created properly. Every now and then I get a PDF from a customer with text to close to the sheet edge or need to move a few things slightly. Pro lets me do that. If you moving to Adobe Create Cloud you get Indesign, Illustrator, Photoshop, Acrobat Pro and much much more. Most of it is not needed for print or design, but you get it all for the subscription price. I do most of my work in Indesign, designing flyers, business cards, postcards, etc.
They haven't been the standard since they got too arrogant and comfortable in their throne of "king position" and stopped developing their software for a few years. At the same time, in their arrogance, they stopped playing nice with school / student discounts. Tie that in with their initial stance of being unwilling to accept that the new fangled "transparency" features Illustrator was starting to launch and you have the recipe for the death of a company / software.
and yes, very sad. I was a Quark baby, it was very hard for me to accept that Indesign had far surpassed Quark in functionality and usefulness.
Affinity software has some equivalent apps without a subscription. Affinity Design = Adobe Illustrator, Affinity Photo = Adobe Photoshop and now in beta only Affinity Publisher = Adobe Indesign. Affinity is on the right track, though I do not use any of their software for live jobs, only to test at the moment. No real interest in changing over from Adobe at the moment till this software is proven and is used by more people in the industry. Currently all our clients (design houses) are using Adobe. When/If they start creating using Affinity software I will start looking at it more. They certainly are a much cheaper option then Adobe with a one time fee (for each application) opposed to Adobe's subscription only plan.
I know that the Adobe crowd will claim that CorelDraw is not a solution - but we have used it for 23 years know to do exactly what openletter is asking. It's not a subscription service (yet!!) but will only run on Windows. Cost is reasonable for what you get. Has worked well for us (smaller digital shop) and may be a good solution for this user too. We do also have CS6 loaded but use Coreldraw primarily to do our design work.