I really enjoyed "The Most Toys" for a lot of reasons. I certainly had no idea about this until some years later and always thought Saul Rubinek did a great job.
So, sorry if I'm missing it but did he complete all his scenes and they chose not to use them, or was it only partially completed when he died and therefore they had to reshoot the Fajo portions?
I also recall reading somewhere that they did "toy" with building the set of his ship for Rappaports size (though I'm not sure how he would have displayed Data in such a small space). Luckily for them they didn't or it's possible the entire episode might have been dumped.
I still think the key moment from this episode is of course when Data is being beamed back and his phaser is in discharge. Did Data lie? Was it simply a natural deduction of his program to attempt to kill Fajo, and it was simply good timing that he didn't end up doing so? To me this is one of the most intriguing questions from TNG and it was a shame it wasn't somehow followed up later.