hey man
it could also be a case of you becoming more aware of the situation that you're in, which is fantastic. some nerves (to a degree) will up your performance levels. with regards to aiming for a greaser, don't worry about that all too much. i haven't flown light aircraft for a while now, but certainly on the heavier jets, greasers aren't necessarily recommended - they reduce wheel spin-up time and consequently burn more rubber. as was said above; aim for a firm touch down, without making it a bounce.
what x-wind method do you use? an old instructor of mine taught me, whenever i'm flying, if i'm using more than 3 fingers to hold/force the control wheel, i'm overpowering the machine. try that out, whilst maintaing control of the situation, (tracking centerline, controlling airspeed) allow the aircraft to respond to gusts, without fighting them. the vast majority of machines flying around the sky are inherently stable, relax and let them do the work, whilst being in control :)