That's the old DH-mod from SteveP99. The current one has M and K switched from that, and is better for staggered boards but not necessarily for matrix boards.

I think the frequency of such rolls may be okay, but if you have weak fingers you may feel it. My best tip would be to train a little! ;-) If you can, play the piano. It's great.

One further tip if your right pinky gets tired is using a Wide mod. That moves some load from the right pinky to the index fingers, and increases hand separation a little which is also comfy.

I can give you example of layout which does not have a heavy pinkies utilization, this is the Russian JCUKEN (ЙЦУКЕН). Most of Russian users share your idea that pinkies are weak and should not be routinely used and should not be involved in frequent rolls. And they are weak indeed without a regular training. Now, side effect of JCUKEN, most of frequent letters are concentrated in the middle of keyboard including the two middle columns. It is not rare in Russian to have 3 or even 4 same finger combos with index fingers. I believe that pinkies are trainable and using them is home row and in home row rolls is for good. After all we have not so many fingers and two many letters to cover to under-utilize either of them.

Russians did not contribute in that layout the same way as American and the rest of the world was just given with qwerty. The JCUKEN layout was invented at the end of 19th century in the USA, as the Russia did not have its own typewriters manufacturing at that time. As a main idea for letters positioning the typographic box with led letters was taken, bigger cells containing more frequent letters is placed in the middle of the box, so the same was done for the layout. This is the "qwerty" of Russian. Many Russians believe that jcuken is ergonomic and it is "not like that awful qwerty", but a little analysis clearly shows that this is a delusion.