You are making this way too hard. The three different installation methods are developer options. The user deals with the method that the developer chose for his/her application. Apple would prefer that all developers used the Mac App Store, which automatically installs applications after they are downloaded.
Things are complicated for you because you are looking for complication. Applications that can be installed by drag & drop are almost always clearly indicated by their developers. Applications that are installed using Installer are also clearly indicated. If they use a custom install file, then the word install is usually part of the name. Double-click it. Easy. If the mounted volume has a .pkg file inside, then you know to double-click it. Again, easy.
A complex process with prompts is still a complex process. OS X eliminates the underlying complexity. With the underlying complexity eliminated, there is no need for prompts. OS X installation prompts are usually require you to agree to the licensing terms of your software. No other decisions are necessary.
You are not running Windows. Stop looking for Windows solutions. Take the time to learn your Mac on its own terms. If you do this, then you too will become a member of that rabid group of Mac users known as "switchers."
Ok first you have you have to stop being so defensive about the Apple OS. I have been using computers since the Tandy, Apple IIe and every PC version since then and a couple of Macs along the way, and for the last 15 yeas as an IT professional mostly in PC. I think I have a decent perspective on what is "complicated or not." The very fact that I had to even ask about these DMG and PKF are proof that the Mac OS still has a long ways to go. I did not invent these different options, Apple did.
I am not looking for "Windows" solutions, just a simple one. And I think you misunderstand so let me explain explicitly: (example)
1. I went to install Avast in an infected Mac, went to avast.com or cnet, forgot which one, and clicked on the download link
2. Apparently after it downloaded, there were no prompts whatsoever. I have many clients that I tutor, especially older people, ad I will guarantee you on my life they will 100% not know what happened to the installation process at this point, STRIKE 1.
3. Since i have competent knowledge of computers, I click on either the downloaded file icon in the browser or I go manually into the Downloads folder and open the downloaded install file. At this point, for another program, it seems there are 2 different kinds of files, i.e., the DMG or PKF. Again as an avg or below avg user, I would have no idea whats the difference and would just double click anyways because thats all that would make sense to me. STRIKE 2
4. Now here, when some installs end, I simply see a mounted drive icon appear on the desktop. With others, I see nothing. With the mounted, I assume I open that, so I do... it opens the program, nice. When I am done, I would like to get that off my desktop and place it on my bottom dock. As usual for this, I drag the mount icon to the dock, but it doesnt take. "I" know why not, but again, most avg users would be very frustrated with this. And I am not making this up, one of my middle-aged clients, a very smart man, was frustrated with this... "WHY CANT I just put this in the dock like the others???" STRIKE 3
5. Now they give up on getting it in the dock. But now they desperately just want it off their desktop, so they drag it into the trash. Well who knew that essentially UNINSTALLS the program.... LMAO. I dont think I need to even further this line of thought.... STRIKE 4
6. Having done this, I install another that is from a PKF. This one places no icon on the desktop. It simply installs in the to Apps folder. Well most people dont have their Apps folders open all the time to see that pop up, so now they might have to guess, what happened... did it install? How do I open it? Then I have to show them they have to go the Apps folder and open it from there... but then they say thats too many steps, cant they just have it in the dock. Then I show them they can drag from there to the dock. Problem solved but this only works for the PKF and is anything but intuitive considering it is not consistent with the way the DMG works. STRIKE 5.
And you talk about the developers "clearly" indicating where things were to be dragged/dropped/installed? I am not sure what programs you were installing but I was dealing with about 4 different common Adobe softwares, Avast, AVG and a couple of anti-spyware programs and a couple of system utilities like Teamviewer (which BTW wouldnt let me install because it was the wrong OS version, LMAO.... wont even let me install an older one), and NOT A SINGLE ONE OF THEM had ANY type of "instruction" on drag/drop or whatever, so I am totally lost on what you are referring to here.
This will be a fruitless argument if you think needing to decipher between a DMG and PKF and then appropriately dragging specific icons to various locations that need to be opened to finally "install" is simpler than clicking "OK/Next" 3-4 times. I cannot debate with anyone who's logic is based on this.
Now for you, someone who has used Macs in such ways where you have gone through all this many many times, any avg human would find that "easy" after so many reps. But as a computer tutor, I dont have the luxury of using someone like you as a baseline. This is REAL WORLD facts and experience, and it is not my concern that you love Macs over PC's or whatever, this is not about that. It is about Mac's claim that everything is "so easy on the Mac and my experience in teaching people about the most basic things on the Mac is anything but, and they have pages of notes just to install a program, much like this thread.
So again, I appreciate your help, u were very thorough in your explanations, but you may want to step back and see this from the commoner's point of view of users out there who think this is anything but an "intuitive process." The users couldnt care less what a developer wanted to do... they just want to install a freakin program and use it from their dock! The worst attitude is that Apple is so perfect and great, its the people who use it that are too dumb or they should learn our ways. This has been their prevalent way of thinking and the base for all their marketing, but most tech savvy people know how crappy Apple products really are in their limitations, and Samsung is finally bring that to the forefront in their recent commercials. and thus you see the drop in % sales between Apple and the Android/PC products. Are these the "switchers" u r referring to? Because in the last 10 years, I have known about 1 switcher from PC/Android to Mac/Apple for every 10 the other way.
I had a similar argument with many Apple fanboys about the mouse cursor accelerator, and it was amazing how many of them tried to convince a ton of us who were having the same problem that it was a problem with US, the user, not the fact that Apple has a perfect accelerator installed in their mouse drivers... actually no, they even refused to admit there was any accelerator, they tried to claim that the PC drivers had the accelerator that was "wrong" and Apple's is how it should be. So forgive me if I have lost total respect for the way Apple fanboys explain how there is nothing wrong with Apple products.