It is seldom, but here I do not agree with Max. I think another solution is objectively better in terms of ergonomics. Pressing the C-key position with the middle finger is the most awkward motion on a standard keyboard IMO. You can do it of course. I typed almost 40 years like that, but when I retrained myself (with a new layout) it become apparent that I should have done that much earlier.
Keeping the same finger positions on a columnar stagger and standard keyboard was one of the must-haves for my custom keyboard layout. I actually have explained that in detail in this article. Look for the animated pictures, which show you how the keys on a columnar stagger and standard keyboard are related. This is one of the relevant animations.
IMO you should indeed use the standard keyboard left side symmetrical to the right side (means pressing the c-key with the index finger). The real problem with a standard keyboard is the top left side, which you have to slightly adjust to, and will not be 100 % symmetrical on a standard keyboard. But you still can use the same fingering than on the right side. You will also find that the B-key has a special role on a standard keyboard. You just should not use it – when you want to be compatible between a 3x5 / 4x6 and a standard row stagger keyboard.
BTW, I stopped using my UHK60 and gave it away in the family. That was after I had tried a Lily58 – now about half a year ago. From the very first moment it was clear that a keyboard must be symmetrical to be most ergonomic and also logic. It felt right from the first second and I knew I never will go back to a standard keyboard. It took a few days, where I needed to get adjusted to it, but it is so much more natural that way, that IMO there is no other way.
I still think a symmetrical standard keyboard with 0.25u row stagger could be a good option – not too different from a standard keyboard. But it does not look like we will ever see that.
Regarding a standard keyboard. I only use that on my laptop keyboard nowadays-- and as explained in the article – works reasonably well, while keeping the same fingering.
I am in the same camp that I would love a UHK60 like columnar version. Wireless would be nice, but is not a need for me. Especially when you need to recharge every few days. There is a keyboard with a single coin cell (Lotus58 unwired), which will last for a year or longer. That is without lights and display of course. I personally find that more interesting than a keyboard with display and lights, which is begging to be recharged all the time. Downside of that one is needing a dongle. Bluetooth would draw to much power.