What exactly do you want the start menu back for? The start button can be configured to send you to the All Apps window, which takes you to a sortable list of all your apps.
This where the difference between 'how I use my computer 90% of the time' and 'the other 10%' matters. A lot. Hugely. As in, it defines whether or not I want to use this over a competitor.
Lets say I want to start the slashot.exe application. In your case and 90% of the user time, you're 100% right. What does the start menu get me over a list of apps that is basically the same as the start men exactly?
What if I want the slashot manual.pdf, linked in the same subfolder as the slashdot.exe application? Ah. Now we have an interface design problem. I could have the manual and the application link both on apps list. But that rapidly clutters the apps list to absurdity with help files, readmes, configuration tools, uninstallers and links to applications I almost never use. I have, for example, adobe creative suite 4 installed, that has (yes literally) 17 sub programs. Of which I regularly use 3 or 4 and the others only rarely. I don't want them in my apps list, I don't want them cluttering up search results. They're adobe programs in the adobe folder of the start menu. Easy to find if needed.
Much more useful than an alphabetical list
here we will have to disagree. Literally nothing is more useful than an alphabetically sorted tree by default. That's the simplest thing people who can read understand.
You can even pull up the (not full screen) search pane directly from the desktop, and search for files and applications in a unified view.
Ah, here we arrive at the next problem. For a number of years MS has had the habit of not putting tooltips with shortcut keys on things. Whomever thought this was a good idea should be fired. Everyone who approved this idea should also be fired. Shortcuts that let you do things only work if the OS tells you what the shortcuts are.
But, no problem, by flailing my mouse around I've manged to find the (unnecessarily) hidden search charm from the upper right. So I search for shortcuts and...
well I get some webpages on shortcuts, including one from MS (and a couple of super sketchy ones), but that tells me how to copy and paste, not windows 8 shortcuts. And because there are no tooltips telling me there are shortcuts, how was I supposed to know to look for them anyway? But I digress, because I already know there are shortcuts I know to try and refine my search to 'windows 8 shortcuts'. Which takes me to a webpage on windows 8 shortcuts. No problem. Except I had to already know it was a feature to search the web to find out how to use the feature. See the problem?
What more exactly do you want?
My start menu on my windows 7 desktop current has 91 subfolders (including several pre-created by MS), and 21 shortcut links. For that much stuff I want some sort of easily manageable default organizational system to it. You know, like an alphabetically sorted tree. Now, I grant you, the habit of creating subfolders based on the name of the publisher of the software is really stupid.
Now lets try another, lets call it simple task. I want to find sirsriresume2013.docx. Which is stored along with sirsriresumexxxx.doc and docx in a google drive folder in user/documents/googledrive/resumes, where xxxx is all of the calendar years from 1998 on. In this case both windows 7 and windows 8 suck badly. I search (start menu and then start typing in both cases, though it's not at all obvious in windows 8 that this will work) and I type sirsriresume and, oddly, both of them find the result for 2006 but not the other ones. But at least that's in the right folder. sirsriresume2012, 2013 etc. produce a 'no valid results' in 7 and just a blank results screen in 8.
So what 'more' do I want? Well, one thing is if you're going to design an interface around your search tools, you need your search tools to not suck balls. So long as *I* was doing the searching in my own hierarchical way *I* could organize however I want, most especially for people who have learning disabilities and can't understand how normal people organize data. I'm a computer scientist without a learning disability, I can organize my data in a way very amenable to computers and to people. But I am not the only market here. Now if search was instant and work that would be one thing. But it doesn't. So... I want my own organization structure until they can get theirs to work.
Now lets do a couple of other things.
Lets say I'm playing a video game or browsing the web, and I decide I need, I dunno, a calculator app. Windows 7, windows key-> type 'calc' hit enter, and it pops up either in a remembered location on or on the panel where the mouse is. Windows 8: if i hit windows key it's taken me out of the other program to the 'metro' UI, I *need* to know to use start + s or start+q. Extra key for worse functionality. What am I getting out of this exactly? Oh and because on windows 8 calculator is a 'desktop' application (thank god), if I was running something in the 'metro' UI... I just got turfed out of it. 'Metro' is a bit like a newsreader for your desktop, or a horrible collection of gadgets in the windows world. It's actually really good at shoveling data at you. It's the sort of thing I'd want on a second monitor along with a web browser and smaller tiles to make everything fit sensibly. Having a single button to swap to it for single displays makes sense.
When most applications (including a lot of the built in stuff) immediately default to desktop mode it's a sideshow, not a centrepiece, and treating it like a centrepiece highlights that it's not suited for that task. If anything the 'metro' UI should be run as an application in a desktop UI element, so I can close it and, 'forward' and 'back' like a web browser etc. Then it would actually be sorta kinda useful. I could put it above or below things on big displays or on a side display if needed. But having this rigid 'metro or desktop' hurts it as a UI element, a lot.
I could go on... and on... and on. But even the people I know who work at Microsoft don't get the message, so I won't belabour it further, here. I see the point, for 90% of the use cases metro is more or less ok. It's an extra step, to get to a full applications list, but that list is reduced in functionality for the rarer cases where I actually need something else. And when I need something else, windows 8 search fails, windows 7 start menu doesn't.
Tested on Windows 7 64 desktop with 2 monitors, up to date, windows 8.1 preview on 5 year old HP touch screen laptop (that works surprisingly well).