Ok, some fun stuff you can try on Spacies on stages with platforms (BF, Yoshi's, FoD). If your chainthrowing in the middle of the stage and you expect your opponent to DI towards the platform to escape, here are some options to follow up:
Try uthrow-> usmash on the last throw BEFORE they'll reach the stage. If they DI towards the platform you can use your normal platform tricks, but if they are at a high enough percent you can Uair into a finisher depending on DI.
If they DI away from the platform you can try for a grab again or just go for an Uair-> F/dsmash.
Another trick I like for racking up damage is to let them reach the platform and than full hop Dair them with a falling Uair as you pass by the platform.
Lastly on FoD, if you get spacies on one of the moving platforms you can juggle them hard with Utilt a few times and typically follow up with the usual Doc ****.
Doc on platforms is FUN!