If your seat feel pretty snugged and firmly tight it’s probably ok
Deep seats are designed to hug your rib cage and upper body, that’s why you have to enter them in an angle sideways, before you sit inside of them.
Anyhow, if you feel that you fit firmly tight, they you may be ok
As for your knee caps and legs hugging the fuel tank goes? Please buy a good set of heel stops, or a good set of foot rests, you’d be surprised on how much they can help knowing that your legs are firmly placed and supported, especially under braking and cornering.
Right now your upper body is doing all the work, and can’t really concentrate in driving.
Try that first. Good luck. Please let us know how it goes.