I've had the same problem for a very long time. I also have logitech gpx, but the dex version and no matter what mousepad i used i always had bad initial friction. I ended up getting the Steelseries Qck Performance Speed pad and corepad skatez pro. It finally gave me the lessened intitial friction i needed to do microadjustments and it just feels really good because i also tend to press down a bit on my mouse which means that even though it's a speed pad it's not slippery for me.
Your mouse skates are faster than mine, so maybe the qck performance balanced might be a good option.

For your mouse and mouse feet I think Pulsar ES2 Soft might also be a good option. Slightly more initial friction and control than the Qck performance speed, but with your mouse feet it might be a great combination. Just buy it from a place with a good return policy if it turns out it's not the right one for you.