I am digging holes to plant saplings. I've been digging aprx. 5 gallon, 10 gallon, and 15 gallon holes for the most part. Most of my saplings are in 1 gal, 3gal, or 5 gallon pots. Smaller holes for bareroots. I either use a trenching shovel or a planting bar for bareroots. I don't seem to have problems with the dibble bars. I have two, the second and the third one in the above advertisement are the exact ones I have. Those aren't heavy.
In the beginning of the day, I use a pick ax with my spade for the larger holes that have lots of rocks. Toward the end of the day... not so much because I get tired and the pick ax becomes too heavy. That's when I jump (please don't cringe) on the spade and start wiggling it back and forth to be able to remove dirt. Admittedly, I am in better shape than most women my age but... I'm not 35 or even 45 years old any longer and I have got to use my weight to get the spades to go down.
For herbaceous perennials, I use a border spade similar to the one at your link but not that brand.
The majority of the areas I am planting into are heavy clay with rock so I need to remove rocks by hand and set aside some of the soil from the hole to be able to amend so I'm not creating a bathtub. I've been using fiberglass handled spades in the $35 range. The one I just broke was a ProGrip Structron. I already threw out the other one but it was another fiberglass handled spade/shovel similarly designed.
For root pruning, I use what ever I've got around but usually (I hear you gasping right now) a very expensive serrated knife that has a handle made out of bowling ball material. The manufacturer is Cutco and I've bought several now just in case I misplace the original one I bought over 20 years ago. I seem to do much better on my knees with the serrated knife when dividing plants than I do with an actual root pruner. I have a decent root pruner, I don't use it much.
For digging large holes I use a round point shovel.
I need to dig holes, lots of holes. Why don't you just suggest two round point shovels for me and I'll try not to act like an ape with them as the day drags on.
editing to add- this is the exact fiberglass handled spade I broke, I had the S700, scroll down a little bit.