They usually only need a nudge rather than a push - I "waddle" them - (made up word !) - what I mean is holding them together, I turn my wrist slightly to waddle one forward 5mm, then the other way to bring the other one level. If I need a bit more thrust I repeat the process
I agree that it's very important in the A320 that there's not to much friction on the thrust levers. You shouldn't have to "waddle" them to make small adjustments. As soon as you push them, they should start moving without "chocks"
A few months ago an A320 joined our fleet, coming from an other company: the thrust levers were way to stiff to permit good manual thrust lever use. It took a few entries in the logbook and a personal chat with the technician to get the issue solved.
So if you need to "waddle" the thrust levers to make small adjustments: make a trouble report sheet!