HI, as mentioned in earlier posts, you should be spending some time with an Instructor who will analise your flying and help you get it right.
If you want to, go to a different instructor for some revision. Some times a different style will make something more understandable.
I just checked my a recent logbook summery and found I have time on 29 dirrerent types of aircraft. Obviously they will all handle differently but the basics are the same.
It seems to me that you may be "overthinking" it.
This is how I do it.
As others have already said, in the circuit, my eyes are outside the cockpit. I use Airspeed and Altimiter to monitor my performance.
Remember the "basics". Attitude controls airspeed and Power controls rate of descent (or climb).
As I turn base I go for my approach speed, if I have the correct approach speed, during the approach I will get a good landing.
I monitor Altimiter while on base to help me find the appropriate power setting. I aim for the magic 500ft but but am not too concerned if I am high. I do not want to be low.
I was taught that after tuning final, to imagine the windscreen as a picture frame. Your intended landing point should not be moving up or down.
Use attitude to hold your approach speed and power to adjust your rate of descent. All I am looking at now is airspeed ( I actually check Altitude at around 300ft). Too slow is dangerous, too fast means a bounce or prolonged float.
My eyes are outside looking at the Picture 90% of the time with glances to Airspeed.
Trim makes it easier to hold the controls. I have only had 1 session of circuits in a Jab, so I am no expert here, but I found I did not have to play with the trim very much in the circuit. Your instructor is best here.
Some aircraft are difficult to land unless the trim is correctly set, I have only flown 3 RA types and none of them were trim critical.
Remember the basics. If the picture is still in your frame, you have it nailed. If it is moving down, you are overshooting. Reduce power and lower the nose to maintain the desired airspeed.
If it is moving up, you are undershooting. Add power and adjust attitude to maintain your desired airspeed.
Once I cross the fence my eyes are outside only working on the flair, crosswind adjustment and hold off.
Remember every landing is different. Different weight, different wind, and you may have traffic forcing you to fly wider or slower than you normally would.
I am no substitute for your instructor, but I hope my thoughts will help you get it!