Hi,
I am the least mechanical person on this forum, however...
When I bought my TF the gear change wasn’t brilliant, so I did 2 cheap fixes which even if they don’t work fall into the category “it needed doing anyway”.
1. I changed the transmission oil, or rather the garage did at the same time as the MOT because I couldn’t loosen the filler plug.
2. And I did do this myself, I changed the two gear linkage bushes, underneath at the rear of the car.