If you're a heavy email user, you should not be using webmail. You should be using a real email client.
Or you aggregate the mail to a single system you access via SSH and GET SHIT DONE. So long as you're using Web protocols to talk to your mail, cut out the complexity of the browser and leverage ssh & screen.
Similarly, if you deal with mail from multiple systems, you can relay/forward it, or aggregate it via multiple retrieval systems (offlineimap is great and synchronizes sent/read mail from numerous locations), but older POP protocols can also work)
I have a daily mailstream that runs in the thousands of messages (many boxes, much complaining, many people, other stuff).
I need an email system that surfaces stuff that matters, fast, effectively, and efficiently, and lets me find, process, and adjudicate mail practically.
If you've never used an efficient and powerful console/CLI mail client such as mutt or mh, you have no idea of the power this provides.
Plenty of Googlers get thousands of messages per day and they use Gmail. There are filters and importance heuristics built into Gmail to help with huge volumes of email. To say "nope, you can't do it that way," flies in the face of reality.
What I can't do is invoke programmatic tools on the web interface itself (at least not without learning a slew of web API stuff).
As opposed to being able to process my local Maildirs with shell tools.
How do you, say, generate stats or view diffs on 84,800 gmail messages? I can do that, trivially, with mutt (tags and commands/pipes) or from the shell outside of mutt.
I still find mutt's filtering notation (~f ~t ~N ~U ~d ... ) to be far more useful and far faster for most use-cases than GMail.
I'm accessing that corpus via both tools right now. Mutt is generally the more useful of the two. One of the advantages, again, of offlineimap is that I've got the option of doing either. And while I'll fully admit that there are some mails for which a full GUI client is more useful, plain text still wins in most instances. And even where I'm not in mutt (say, on an Android device), straight text virtually always wins.
I'll also admit to using GMail's filter rules to classify my mail, though they have problems, most notably the inability to un-archive specific messages, or to re-order / order filters at all. At least so far as I've discovered.
They're still generally better than Microsoft's pants mail rules.
And there are the devices on which I get shit done.
Mail app on my phone, with filter rules, keeps most of the useful stuff front and center.
It's trivial enough to copy an ~/.offlineimaprc and ~/.muttrc across Linux systems (or Macs FWIW) for everything else.
Sure, if I absolutely need to I can log into Gmail through a web interface on another system. With user/pass auth, that means, though, that I'm extending my security envelope to include whatever exploits that machine may have. Given I've got the Internets in my pocket these days, that's pretty much never necessary.
Yes, that includes mutt and mh.
What's your job?
What's your use case?
I'm a technical director at a media agency, but the vast majority of my e-mail is stuff that goes to my personal account, related to various open source projects and my other things I do in my spare time - my work e-mail is maybe 5% of my total e-mail volume.
My use case is accessing my e-mail from 10+ different places, some of which I don't have decent shell access from (such as my phone, where a console based, key based client is out of the question), combined with heavy use of labels and priority inbox.
I gave up on console based e-mail clients about 12 years ago, when I co-founded a webmail service. Never looked back.
In my case, most of the messages are system alerts, logs, notifications, etc., along with human-generated messages, reminders, etc.
Some I can ignore, some I've got to have at least a gist of what they contain. Trending patterns in others can be very valuable.
For all of these, a console client generally offers major wins over webmail, as I've described.
No thanks. I like being able to pick up my wife's laptop and check email effortlessly.
I'm not saying that you wouldn't be able to do this with a web-based mail client, but I think that the machinery to do that would be less natural. (My sense of what is natural might be warped, though.)
Also, there is much to be said about the ability to customize your mail client to suit your needs. The very fact that people are complaining about Gmail's new design shows that a lot of people are relying on Google to tell them how they should manage their email, and try to adapt their needs to the tool rather than the other way around. This is not a technical limitation of web-based mail clients, but most webmails I know aren't really hackable.
In fact, using gmail should take fewer strokes than that. Assuming you have a keyboard shortcut to spawn a gmail window, enter will take you to the first message, and 'e' will archive that message. Command-Q/Alt-F4 to quit.
Labels can be applied with an 'l' and the label name, next/last message is 'n'/'p'.
The full list of keyboard shortcuts is available here: https://mail.google.com/support/bin/answer.py?answer=6594
It would, of course, be better if they let you customize the shortcuts and sped up the loading of the initial page.
Go to Labs and enable Custom Keyboard Shortcuts, then go to town! I changed a bunch of my shortcuts, for example an operation I do quite often is "select all unread, them mark as read." But I couldn't remember the shortcuts they assigned - they didn't seem mnemonic at all. I changed them to SU for Select Unread and MR for Mark Read. Bingo!
Those were the main things I had in mind (along with adequately customizable desktop notifications). As for shortcut customizations, the Labs feature isn't as good as a configuration file in my opinion (slower to edit, harder to share, harder to diff, etc.). As for the loading of the initial page, I still wonder why it takes so long... You could probably get a nice setup by keeping a Gmail window open and assigning a shortcut in your WM to display this window, but it's not a common feature in WMs.
(If you are big on "Inbox Zero" that's not an important feature, but here email backlogs often serve as another type of reference, complimenting our wikis. It sounds awful, but in practice you wouldn't really want to commit a lot of information to a wiki that is priceless for a week and trash thereafter)