Welcome... and yes, for those of us who are not satisfied with the original Colemak D and H in the centre column, the DH mod is the perfect solution.

There has been a contribution for OS X previously, but not being a Mac guy, I have no idea whether this is compatible with Sierra. There are some Mac users around on the forum though so hopefully someone will chime in.

Your typing speed is already pretty good - anecdotally those with a good touch-typing technique at the start seem to transition faster. But apart from the potential increase in speed, the improvement in comfort is a huge, and even more worthwhile, benefit.

Hmm, it's probably my best bet to try some hardware (UHK, maybe?) where I can try to program the Colemak-DH mod in, along with the Caps Lock > Backspace part (which, after reading further into this, I can do using a combo of Sys Prefs > Keyboard and Karibiner - Elements). I'm now on Week 3 of practicing the standard Colemak layout on my MacBook Pro, and I'm averaging between 50 - 60 WPM on 10FF, Typeracer, and NitroType. I'm "slightly uncomfortable" with the D and H standard positions at the moment, a feeling that may or may not disappear after more practice. I will be incorporating Colemak at work, starting tomorrow, and see what happens. If the discomfort with the D-H keys persists, I'll probably try the hardware keyboard route and set enough time aside to adjust to the DH mod. If I do end up buying a programmable keyboard, though, which one will work better for me since I tend to prefer the Magic Keyboard's scissor switch? Will the cherry reds suffice?

And also, does learning the standard Colemak first and switching to the DH mod later require a short adjustment period, as in 1-2 days? As much as I'd welcome the additional comfort on my fingers and hands, I do not want to sacrifice my productivity at work.

Nearly all DH modders would have started with standard Colemak, including myself. It does take a short period of readjustment, as you would expect. The effort in learning Colemak first is not really wasted though, since DH builds on standard Colemak for the most part. The only exception is G - just as you are getting used to its Colemak position, it reverts back to the Qwerty position in Mod-DH.

A programmable keyboard is good potential solution, as long as you don't mind carrying it around - the UHK does look fairly portable at least. The Mistel Barocco  is another option. Or if you wanted to go down the matrix-like programmable keyboards, there's also the Planck.

I have one of Hasu's USB-USB remappers also, and would recommend it. It is handy in situations where you need to use an unfamiliar computer/keyboard and can't easily change the settings, and DreymaR has created DH-friendly mappings for it.

Thank you for all the helpful suggestions! Despite practicing a lot via the sites I previously mentioned, the real test was typing standard Colemak at work. I believe I did well, although slower in speed (around 45 WPM with 97% accuracy) for the first day. I'm sure I'll improve as I continue on my regular, day-to-day typing tasks.

The Hasu device combined with the Magic keyboard, a BT dongle, and USB hub seem a bit clunky for me since I prefer a more portable, streamlined setup. I'm honestly not that great in putting together a keyboard myself, so the Planck is out. Not sure about the Mistel Barocco, but I'm liking the additional key cluster and trackball modules with the UHK split kb setup. I do plan on using whatever keyboard I do purchase with a dual iMac (work) plus the occasional MacBook Pro (personal) setup, so do you think that the UHK configuration will work? And oh, will using that with cherry reds present more pressure? I do prefer using key switches that require as little pressure from the fingertips as possible.

I'm currently using a Rollermouse with my Magic Keyboard if that helps. Using a regular, even a vertical mouse, just makes the pain on my wrists and arms worse. I've tried using trackballs on each side of the keyboard, but that's too clunky when switching between computers.

I have no soldering experience whatsoever haha. I researched all the keyboard suggestions mentioned on this thread so far, and for my needs, I'm leaning toward the UHK one combined with the cluster and trackball modules. If Hasu ever makes a device that's suited for Bluetooth keyboards (Apple), then I'll most likely purchase that instead to use with my current hardware, especially when traveling.

Come to think of it, the Bluetooth is built into my iMac. I'll need a smaller USB hub, though.

Update: Not sure why. My typing speed at work went down to about 52 WPM while using regular Colemak. For some reason today, I kept pressing the wrong letters at times. I am trying to focus more on my accuracy, though.