What are some simple additions or improvements you've made to some (or all) of your Lego sets?

For me since I really liked the stone footprint form the T-rex skull set I decided to just get the parts to build it via Lego's pick a brick so that I can display i t next to the T-rex skeleton set. Since it feels kind of pointless to buy the entire skull set just for the footprint build. Especially when I already have the bigger full skeleton set. And with the Jaws set while I do like the inclusion of the smaller side build with the stand allowing you the potential to have a fully complete...