There are many techniques to fixing cars. Your technique s**ks.
I need to be harsh because I see this so often. You seek help to guess at what is your problem. If this has to be your technique of choice then I can be of no help.
If you wish a scientific approach there are many, but the first requirement is to find out what is missing! Is your problem fuel? Or is it ignition? Since you don't have the proper equipment (ignition scope/fuel pressure gauge) you will have to be creative.
You might take an old spark plug and widen the gap and hook a plug wire to it laying it on the metal of the engine while someone cranks the car. You will get a qualitative NOT quantitative answer.
To guess at fuel pressure I would suggest pulling one injector attached to its pipe and bypass the fuel pump relay and depress the airflow plate. The injector should throw an appropriate stream of fuel regulated by how far you have depressed the airflow plate.
****NOTE**** doing this test fills the intake with fuel SO the test should only be done briefly**********Note fire hazard also.
Bosch Master, ASE Master, L1
33 years MB technician