I think those two were important to Rose. When Jasper saw Steven (whom she still idiotically thinks is Rose) she practically radiated malevolent glee and bragged about what she had.
yes i agree but i dont think she was mastaking when she called him rose (and yes i know what you meant and it is a mistake to call him rose for many reasons but their are still some simillarties and of course she doesnt know the full story of steven,rose,greg) first off two of her powers steven atleast of which are confirmed steven and rose share which is the shield and the floating power,both of their powers seem to tie to their emotions in the episode steven float he learns his floating power is tied to his emotions and we see that in rose as well in greg the babysitter when she jumped to save greg and baby sour cream she used her floating powers and when she knew greg was in danger and understood the sitaution better she saved him atleast thats what i assume and alot of pepole say, also he does own 3 things she did which is her gem,her sword (despite not really using it well maybe if he fuses with connie and they form stevonnie he will use it or more correctly they will use it) and her lion also Technically she is part of steven also i remember something one character said im not sure who did i think one of the crystal gems:our body is only an illusion.
so yeah sorry i took it to seriously also another thing i wouldnt brag about those two if i were her just think about it this way most of the crystal gems either were corrupted or probably got cracked so much they in the end didnt even exist and now there is 5 crystal gems including peridot (also i know about bismuth but i dont know what will happen in the episode so im not gonna make that assumption yet, and i know the whole deal with lapis but i think she has her ways to go until she will forgive the crystal gems for what they did also peridot herself has her ways to go as she is just a novice funny kind of like what steven was in the very very beginning).
also just remember she didnt die just gave up her physical form to crate steven so she is still alive just her physical form isnt she is litterally part of steven so i dont think its such mistake by jasper but yeah it isnt 100% becaue a. he is a hybrid,b.probably has access to more powers or more depth with his powers for example fusion with humans something rose most likely couldnt do and finally c.he is less experinced then she was also never experinced the war.