( this is an answer which will be given alongside a disclaimer that i have only seen spectre once, and during my first and only encounter with the film i had been looking for silva the entire time and therefore had only been half paying attention to the plot. ) i find that raoul silva would feel particularly indifferent towards ernst blofeld in the fact that he is a contributor and nothing further. he has no genuine interest in blofeld’s endeavors, or in spectre even in a general sense, besides the fact that they were more than likely supplying him with financial aid and very possibly, also, with man-power ( i.e. henchmen ) silva often displays a pretty serious sense of pride regarding the fact that he is relatively unaffiliated with any specific group, potentially because he spent so many years deeply involved with MI6 just to be -- metaphorically speaking ( or is it? ) -- fed to the wolves. he takes orders from no overseer, and basks very heavily in the freedom of picking his “own secret missions” without having any large amount of concern regarding being betrayed. therefore, i doubt blofeld would hold any serious interest, outside of the aid he is accepting from him and his organization to seek revenge on m. i do, however, think it very possible that he MAY have been more interested had he survived the events of Skyfall. with m dead, there would be very little to drive him; and spectre might have offered some sort of sanctuary to him in exchange for his technological capability.. nevertheless, i doubt he’d remain closely affiliated very long; being somewhat “free agent” is much too appealing, and blofeld is very keen on casting the shadow of a puppeteer, which would collide with any other dominant personality: particularly silva’s.