Would it be worth it? Generally speaking, no. Your typing flow won't – shouldn't at least! – hinge on one or a few symbols no matter what. In my opinion, one should learn to keep a relatively good flow even when typing complex text with symbols. That's part skill, part mindset I believe.

If you switch languages, you'll have to switch the meaning of your key accordingly. I guess that'd lead to confusion and take at least as much mental focus as the annoyance over a relatively frequent symbol in a less-than-optimal position?

One should not use the standard locale (non-US/UK) layouts when coding, in my opinion. On the Norwegian layout for instance, ^`~ are only accessible on dead keys which is a right pain. My Universal Symbol locale layouts all have the expected symbols in the expected positions if you're used to the US layout. And that's pretty much a standard when thinking coding symbols.

If using a ligature/macro compatible mapping system, one might consider making a few boilerplate macros instead, in easily reachable locations. {Semicolon, Enter} is a simple one.

You lucky bastard. The Norwegian layout has it on AltGr+2. The travesty.

Indeed, most of your coding speed will not stem from typing flow alone, as it's a lot of on-and-off typing and editing. In my opinion, Extend (or something similar) is your friend there.

when I say my @ is above the 2, I only mean in terms of what happens when I press it... the keycap is printed " in the british style

but large portions of whats printed on my keyboard keycaps bear little resemblance to what happens when you press them..

shift is far easier for me, but thats probably because I have simply pressed them many millions of times more the alt gr

Typing anything longer than a couple of sentences into in web window is a setting up for a fail anyway. How many times have you typed something into a web form, pressed "save" or "send" or whatever, only for the session to have timed out, or there to be a server error. That has even happened to me on this forum!

If it's a long text, better instead to type it in a text editor, and then just paste it into the form when ready.

i'm not sure what text editor you use, but if emacs then take a look at yasnippet

emacs has automatic commenting built in based on the file mode, bound to M-;

I agree that Alt-Gr is very useful. Being french, I'm already using it for: àôéîèèâɛêäöëï (to be typed by the left hand, same as Dvorak's voyels).

Regarding symbols to be typed by the right hand, I'd need a home key to be reachable by the left thumb and I don't have any (osx). I thought about remapping caps-lock to alt, but that might be heavy on the left pinky as I'm already using caps lock for `esc` in vim/evil.

Something else that I have in mind is to map numbers under the right-hand while holding capslock. I really hate writing numbers (such as "0961") using the upper row and thought that have a kind of numeric pad right under my right-hand might be easier on the fingers.

Have a look at my Extend layers (in my signature topics). I've made a NumPad layer but I don't think it's implemented for Mac as opposed to Extend1. I'm in the process of testing it out on protracted number entry sessions these days, and so far I like it well enough although it takes a little getting used to.

I've learnt some things, for instance:
• There should be two 0 keys like the broad one on a NumPad. This makes it easier to enter for instance '10' or '00' which are frequent.
• I need an accessible colon key for time entries (10:00, 09:30 etc – for my list of work hours!).
• A nav/edit block is very useful and although it's a bit confusing to move it to the left hand it's still nice

    DreymaR's Extend2 layer:
 * ,----.    ,-------------------. ,-------------------. ,-------------------.
 * |    |    |MPau|MRwd|MFFd|Ejct| |WRef|BriD|BriU|Slep| |www |Mail|App3|App4|
 * `----'    `-------------------' `-------------------' `-------------------'
 * ,-------------------------------------------------------------------------.
 * |    | !  | @  | #  | $  | %  | ^  | P7 | P8 | P9 | P* | P- | =  |        |
 * |-------------------------------------------------------------------------|
 * |      |Home| Up |End |Del |Esc |PgUp| P4 | P5 | P6 | P+ | (  | )  |      |
 * |-------------------------------------------------------------------------|
 * |*Ext2* |Left|Down|Rght|BSpc|NLck|PgDn| P1 | P2 | P3 |PEnt| '  | ,  |     |
 * |-------------------------------------------------------------------------|
 * |     |    | ^Z | ^X | ^C | ^V |Btn1| :  | P0 | P0 | P. | P/ |            |
 * |-------------------------------------------------------------------------|
 * |      |     |     |                             |Ext2 |     |     |      |
 * `-------------------------------------------------------------------------'