JazakhaLaHu khairan malam... But be weary on classifying hadith as either been authentic or not.. Without established facts.
Your number 18 on salatul tasbih.. Sheikh nasirdeen albany graded the hadith as sahih though the hadith has only one chain of narration but he graded it as authentic .
It is similar to the hadith on Niyya or intention (innamal aamalu bin niyyat.......) related by only one chain but this doesnt make it less authentic.
Secondly ibn taymiyya was asked about this salat..
He didnt discard it as daeef neither did he approve of it.. He but encouraged the people to do other ibadat that are established to be saheeh..
My point.. Though the salat is not very popular you cant classify it as daeef expecially when scholars of hadith like albany thinks otherwise.. May Allah forgive them and us all.
Allah knows best