Add a check for the destination of a player-issued TP request to ensure the player is standing on a full solid block.
Could result in an error message for both parties if standing on a partial block that could end up putting the player underground.
The teleports already have a wait time and I don't think TP requests are incredibly frequent, so shouldn't add too much trouble.
Might also add a check when using /sethome and /set$ since they could result in similar issues

I don't know if this is going to have the fully intended effect that you want.

If a player makes a change...puts down carpet lets say...AFTER they do the /sethome how would you give them an error?