Another thing's weight. Critical not only on the take-off obviously, but landing too. It puts your stall speed up and can leave you wallowing at speeds where usually you are nicely in control and the plane feels good. Read Stick and Rudder for a nice round-up of low speed handling (and everything else too).
Your aircraft light and your aircraft heavy are two completely different machines, confused at your peril.
Cheers,
QDM