I think the end of this video is most important.
When he says: When you want to check your work, and see how close your model is, you can measure some dimensions that we did not measure
And: That is off considerably, but what you can do, you can tweak your numbers, and double check

I noticed he did not then use the dimensions available in the Jig Setup dialogue box
Where many dimensions are related to tube junctions, and not the more easy to establish end of tubes

No, Joe does his checks with custom dimensions
Custom dimensions are great.
But you have to redefine them after every adjustment of your model.

My question:
Will it be possible to add some standard dimensions to BikeCad with which you can check your real bike meaurements?

I would like to propose:
Saddle clamp both to top and bottom of Head tube
Saddle clamp of ground (Saddle clamp to BB (Y) is already in the Components/General dimensions box)
BB to top of Head tube direct (BB-HT bottom direct is already in the Jig setup dimensions box)
Top of Head tube off ground (BB-HT bottom (Y) is already in the Jig setup dimensions box)

Note; I prefer the saddleclamp above the saddle.
Because the saddleclamp is less prone to Parallax Angle
The saddle is not flat, it is placed for and aft, etc
And there is always the very difficult to know Saddle reference point X and Y in Bikecad.

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When you know your way in BikeCad, a lot of the dimensions you use to model a real world bike are already there.
In addition to a very affordable but inaccurate digital angle gage, I always make marks on the ground, vertical below the wheel axes, vertical below the top of HT, vertical below the BB, vertical below the saddle clamp etc
The Jig Setup dimensions box will then offer me great checks like Chainstay horizontal, Front-center horizontal.
The Frame dimensions box will offer me Reach
The Components/General dimensions box will offer me Saddle clamp to BB (X)

In the attached picture below you will see the dimensions I used to document a real world bike in BikeCad.
I could not use an angle gage.
The blue numbers are measured dimensions.
The dimensions calculated by BikeCad are in black.