*Consider lowering the drag factor: You are a big guy, but I'd still set your damper lever a bit lower so you get a feel for the leg drive and speed, atleast initially. You can check drag factor and set it to 110. Right now, based on the lever position I think you are on 150.
*Lower your feet one hole so your heel sits lower.
*Heel lift is not a problem on the recovery into the catch, do not worry about it, that is an idea propagated by Dark Horse but it really isn't something to worry about.
*When you drive out of the catch, your heels should come down and your weight should press hard into the midfoot and heel. You should hold the handle loosely and feel the pull against your arms as your shoulders, arms, and hands provide the connection point.
*Drive hard with the legs and do not use your back and arms until your legs are fully extended or are very nearly fully extended, then you open up the back, and lastly finish with the arms. When you drive with the legs you should feel the pull against your arms, but keep your arms loose. The goal is to keep the handle accelerating until it finishes against your torso. Your arms should do less work and your legs should do more work, as the legs are stronger and more resilient to fatigue.
*Try to pull the handle slightly higher (just below nipple line). When you do this, you will also open your back a bit more.
*When you return from the finish, try to not lean as far forward into the catch and also avoid collapsing your torso into the catch, plank exercises might help.
*You can also try to deliberately slow down a bit on the recovery so you aren't racing back to the catch.
*Your abdomen isn't braced enough and collapses as you finish the recovery and approach the catch. Similarly, when you drive with your legs, keep your abdomen braced to avoid losing energy into the spine and also prevent back injury.
*The center of mass of your torso as you return should also be over the seat rather than in front of the seat.
*Take a look at these two videos
https://youtu.be/VE663Kg0c00
https://youtu.be/JLyOyWls9_Y
In the first video, the rower demonstrates fantastic form. He uses legs, body, hands on the drive and then hands, body, legs on the recovery. The coach breaks this movement down into basics and the rower shows how it can all be integrated into a smooth powerful stroke. As the rower increases his strokes per minute, the form does not change.
In the second video "Maximum power on the rowing machine", there is a section (~10 mins in) that describes a weak catch that slips the flywheel's clutch rather than engaging the flywheel fully. That is why you don't feel the resistance until late in the stroke. Because your leg drive is too slow and lacking force at the catch, the chain extends a bit without fully grabbing the flywheel. A lower damper setting will help feel this connection, as will the 1 foot in drill shown in the video (about halfway into it).