Assuming a 10:1 compression ratio = 150 psi. (the only compression related data was for a corrected CR of 6.0:1).
Also assuming that the 1.5 mm plate is sandwiched between 2 base gaskets, the actual increased height is closer to 2mm.
Recalculating the CR, it drops from 10:1 to a lower 7.17 CR and a new compression of 107psi. That is a loss of 43psi for using the plate.
A rule of thumb: engine requires ~100 psi to run. Obviously the engine with the plate & gaskets still runs, but a loss of ~43psi demonstrates the need for the cylinder to be decked ~2mm just to maintain stock compression.
At least raising the exhaust port to a 21' to 23' BDT can be easily accomplished.
On larger engines an increase .001" of deck height = a loss of 1psi. In this example .002" = 1psi.