avoid putting ALL your key openings in one sketch,
My workaround is before I do anything, I put common dimensions in the User Parameters like:
MX_opening = 14.00mm, U_spacing = 19.05mm, etc...
then pick a specific spot and constrain it to the origin, upper left corner of the ESC key, for example, and start the sketch, and put your only necessary keys dimension-ed in terms of multiples of U_Spacing (e.g. 2*U_Spacing) to that spot.
For your layout I would only include 1U openings for:
ESC
Tab
Caps
LShift
LCtrl
(Split)Space(s)
The few keys right of Space
BS
Enter
backslash
RShift
Arrows
Column on the far right end and the 2 upper right keys
A second sketch of the stabs, hit P to reference the locations of the first sketch and snap the stabs to them.
And a third Sketch consist 1U openings of:
F1 F2 F3 F4 (or F1 only)
1
Q
A
Z
Then a forth sketch for the plate outline
Make the plate, extrude all the openings from first and second sketches except LCtrl.
Extrude again for Ctrl and use Pattern Features
Direction to the right
Count: 3
Spacing: 1.25*U_Spacing
Repeat the same for F1/1/Q/A/Z
THEN you can make a new sketch, project the actual shape of your plate and export your DXF if you need to.
Yes it's freaking tedious.
No don't do pattern in sketches, or at least avoid if possible.
Same as above, leave corners sharp and do the fillet to the solids as editable features, not sketches.
It's actually good to fully constrain your sketches.
Plan your "operations" beforehand and try to do it wisely.